3306B Industrial Engine Caterpillar

Either too much fuel for combustion or not enough fuel for combustion can be the cause of a problem in the fuel system. The source of the problem is difficult to find, especially when smoke rises from the exhaust. Therefore, work is often done on the fuel system when the problem is really with some other part of the engine.

When noticeable smoke rises from the exhaust, this problem can be caused by a defective fuel injection valve. However, this unusual smoke can also be caused by one or more of the following reasons:

• Not enough air for good combustion

• An overload at high altitude

• Oil leakage into combustion chamber

• Not enough compression

• Air inlet and exhaust leaks

• Retarded timing

Note: Refer to Testing and Adjusting, "Troublshooting" for more information on the fuel system.

Fuel System Inspection

A problem with the components that send fuel to the engine can cause low fuel pressure. This can decrease engine performance. To inspect the fuel system, follow this procedure:

1. Check the fuel level in the fuel tank. Inspect the fuel tank cap. Ensure that the vent is not filled with dirt.

2. Check the fuel lines for fuel leakage. Ensure that none of the fuel lines have a restriction or a defective bend.

3. Install a new fuel filter. Clean the primary fuel filter.

4. Remove any air that may be in the fuel system.

   If there is air in the fuel system, use the priming pump to open the drain valve on the fuel injection pump housing. Drain the fuel system until fuel without air flows from the drain line.

Follow these steps when you drain air from the fuel injection lines:

1. Loosen the fuel line nuts on the fuel injection valve by 1/2 turn.

2. Move the governor lever to the LOW IDLE position.

3. Crank the engine with the starting motor until fuel without air flows from the fuel line connections.

4. Tighten the fuel line nuts.

Note: The fuel priming pump will not provide enough pressure for pushing fuel through the reverse flow check valves in the fuel injection pumps.

Checking Engine Cylinders Separately

If any of the following conditions occur, check the individual engine cylinders:

• The engine runs rough.

• The engine misfires.

• The exhaust system blows out black smoke.

Use this procedure to check the engine cylinders separately:

1. Run the engine at an rpm that gives the maximum misfiring or rough running.

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NOTICE
The fuel injection nozzles can be permanently damaged by twisting if only one wrench is used to loosen or tighten the fuel line nuts. Use one wrench to hold the nozzle and another to loosen the nut.

2. Then, loosen a fuel line nut on the fuel injection nozzle for each cylinder one at a time. This will stop the flow of fuel to that engine cylinder.

   When a fuel line nut is loosened, the misfiring or rough running should increase.

3. Tighten the fuel line nut.

4. Repeat Step 1 through Step 3 with each engine cylinder in sequence until you discover a loosened fuel line that does NOT affect the engine's performance.

5. When you find the engine cylinder that does NOT affect the engine's performance, perform the following operations:

   1. Test the fuel injection pump for that cylinder.

   2. Test the fuel injection nozzle.

When an engine runs at low idle rpm, the temperature of an exhaust manifold can indicate the condition of a fuel injection nozzle. A low temperature indicates that no fuel is reaching the cylinder. This can possibly signify that the fuel injection nozzle has a defect.

When an engine runs at low idle rpm and the temperature of an exhaust manifold is at an extra high temperature, too much fuel is probably flowing into the engine cylinder. This can also signify that the fuel injection nozzle has a defect.

The most common defects on fuel injection nozzles include the following defects:

• Plugging or blocking by carbon on the tip of a fuel injection nozzle

• Orifice wear due to abrasive particles in the fuel

• Wear from a wire brush on the fuel injection nozzle's tip

Refer to Special Instruction, SEHS8149 for the procedure for checking the temperatures in the exhaust manifold port.

Testing Fuel Injection Nozzles

Table 1

Required Tools
Part Number	Part Name	Qty
5P-4150	Nozzle Testing Group	1
5P-7448	Adapter	1
8S-2270	Fuel Collector	1
FT-1384	Fuel Collector Extension	1
8S-2245	Injector Cleaning Tool Group	1
8S-2258	Brass Wire Brush	1
6V-4979	Carbon Seal Installation Tool	1
6V-6194	Needle Nose Pliers	1
5V-2170	Tube	1
9S-1742	Hex Set (9 piece)	1
6V-6088 (1)	Calibration Fluid 19 L (5.0 US gal)	1

( 1 )

You can also use 6V-6067 Calibration Fluid .

6v-6067 Calibration Fluid

Note: See Special Instruction, SEHS7292, "Use of 5P-4150 Fuel Nozzle Tester 8S-2245 Kit" for more information.

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NOTICE
Do not use dirty test fluids when you test fuel injection nozzles. Also, do not test fuel injection nozzles unless you have the correct service tools.The use of dirty test fluids and the use of incorrect service tools will result in damage to fuel injection nozzles.

Caterpillar Inc. recommends the use of Calibration Fluid (SAE J967) for testing the fuel injection nozzles. The temperature of the test fluid needs to be from 18 °C to 24 °C (64 °F to 75 °F).

Illustration 1	g00301875
5P-4150 Nozzle Testing Group (1) 5P-7448 Adapter (2) 8N-7005 Fuel Valve Nozzle (3) 6V-2170 Tube (4) 8T-0859 Pressure Gauge (5) FT-1384 Fuel Collector Extension (6) 8T-0856 Pressure Gauge (7) Gauge protector valve for 8T-0859 Pressure Gauge (8) 8S-2270 Fuel Collector (9) Gauge protector valve for 8T-0856 Pressure Gauge (10) On/Off valve (11) Pump isolator valve

Illustration 2	g00314004
Extra Valve (12) Gauge protector valve must be in the OPEN position at all times.

Do not disassemble the fuel injection nozzle for cleaning or for adjustment. Use the following tests to determine if the fuel injection nozzle's performance is acceptable:

• "Valve Opening Pressure Test"

• "Flush the Fuel Injection Nozzle"

• "Tip Leakage Test"

• "Orifice Restriction Test"

• "Leakage Test for Air Purge Screw"

These tests follow immediately.

Performance Tests for the Fuel System

Preparing the Fuel Injection Nozzle for Testing

Illustration 3	g00314003
Removing a Carbon Dam (13) Fuel injection nozzle. (14) Carbon dam. (15) Seal.

Before fuel injection nozzle (13) can be tested, remove all loose carbon around the tip of the nozzle.

Illustration 4	g00314152
8S-2245 Injector Cleaning Tool Group (16) 8S-2258 Brass Wire Brush. (17) 6V-4979 Carbon Seal Installation Tool. (18) 8S-2250 Nozzle Holding Tool .

Clean a fuel injection nozzle with 8S-2258 Brass Wire Brush (16) .

1. Remove carbon dam (14) with needle nose pliers.

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NOTICE
Do not use a steel brush or wire wheel to clean the nozzle body or the nozzle tip. Use of these tools can cause a small reduction of orifice size, and this will cause a large reduction in engine horsepower. Too much use of a wire brush will also remove the coating that is on the fuel injection nozzle for protection.

2. Remove seal (15) from the fuel injection nozzle.

3. Clean the groove for carbon dam's seal.

4. Clean the body of the fuel injection nozzle below with 8S-2258 Brass Wire Brush (16) .

5. Carefully remove the carbon, but avoid damaging the fuel injection nozzle's body with the bristles of the carbon brush.

   Note: A change of the color in the area below the groove is normal. This does not affect the body of the fuel injection nozzle.

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Illustration 5	g00314154
Fuel Injection Nozzle (19) Air purge screw and seal.

6. Remove the air purge screw and seal (19) .

   Note: The air purge screw and the seal must be removed for all tests except the "Leakage Test for Air Purge Screw".

Valve Opening Pressure Test (VOP)

Illustration 6	g00314156
Fuel Injection Nozzle (Test) (7) Gauge protector valve. (10) On/Off valve. (11) Pump isolator valve.

1. Install 6V-2170 Tube (3) to the tester.

2. Install fuel injection nozzle with 5P-7448 Adapter (1) .

3. Position the hole for the air purge screw toward the tester. This hole should be in line with 6V-2170 Tube (3) .

   The fuel's spray pattern will be horizontal.

4. Point the fuel injection nozzle's tip downward.

   Ensure that this nozzle's tip extends into both the FT-1384 Fuel Collector Extension (5) and the 8S-2270 Fuel Collector (8) .

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Ensure that you wear eye protection at all times during testing. When fuel injection nozzles are tested, test fluids travel through the orifices of the nozzle tip with high pressure. Under this amount of pressure, the test fluid can pierce the skin and cause serious injury to the operator. Always keep the tip of the fuel injection nozzle pointed away from the operator and into the fuel collector and extension.

Note: Place a shop towel around the upper part of the fuel injection nozzle. This shop towel should be used to absorb any fuel leakage.

5. Close on/off valve (10) .

6. Open pump isolator valve (11) .

7. Open gauge protector valve (7), and use the pump to create a slow increase in pressure. Continue operating the pump until the fuel injection nozzle begins to open.

8. Read the maximum gauge pressure at the instance when the test fluid flows from the fuel injection nozzle's tip.

   Note: While the pump isolator valve is opening, the pressure reading on the gauge can drop quickly. The check valve will make a noise at the same time. The gauge's pressure reading might remain constant when the check valve in the fuel injection pump opens.

   Note: The check valve can make noise when the check valve is in good operating condition. The check valve can also spray a coarse vapor from the nozzle's orifices in Step 8.

   If the opening pressure does not meet specifications, do not use the same fuel injection nozzle again. Review the specifications in Table 2.

Table 2

Specifications for VOP

16,200 to 18,300 kPa (2,350 to 2,650 psi)

Flush the Fuel Injection Nozzle

1. Close gauge protector valve (7). Also, close on/off valve (10) .

2. Then, open pump isolator valve (11) .

   Note: Ensure that the fuel injection nozzle extends inside the top of FT-1384 Fuel Collector Extension (5).

3. Operate the pump rapidly for three full strokes.

Tip Leakage Test

1. Use a clean cloth to remove all the fuel from the fuel injection nozzle's tip and from the body.

2. Place a clean cloth around the body of the fuel injection nozzle. Use this cloth to catch any fuel leakage from the air purge screw's hole.

   This will help prevent any fuel leakage from draining into the fuel injection nozzle's tip.

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Illustration 7	g00314156
Fuel Injection Nozzle that is Ready for Testing (7) Gauge protector valve. (10) On/Off valve. (11) Pump isolator valve.

3. Open gauge protector valve (7), and close on/off valve (10) .

4. Then, open pump isolator valve (11) .

5. After you create a pressure of 1380 to 2000 kPa (200 to 290 psi) less than the opening pressure that was measured in the VOP Test, hold this pressure for 15 seconds. Count the number of drops that fall into the fuel collector.

6. Record the number of drops that fall. Compare the number of drops that are counted with Table 3.
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   Table 3

   Tip Leakage Specification

   No more than 5 drops should fall in 15 seconds.

7. If the nozzle is not within the specifications, DO NOT USE the nozzle.

Orifice Restriction Test

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Illustration 8	g00314156
Fuel Injection Nozzle That Is Ready for Testing (7) Gauge protector valve. (10) On/Off valve. (11) Pump isolator valve.

1. Close gauge protector valve (7) and on/off valve (10) .

2. Then, open pump isolator valve (11) .

3. Point the tip of the fuel injection nozzle into the extension and toward the fuel collector.

   Position the hole for the air purge screw toward the tester. This hole should be in line with 6V-2170 Tube (3). After this positioning, the fuel injection nozzle should be 15 degrees from vertical, and the spray pattern will be horizontal.

4. Create a rapid pressure increase, and look at the orifice discharge when fluid begins to flow through the fuel injection nozzle.

   In fact, look at the shape of this discharge. There should be a similar discharge through all nine orifices or six orifices. Any vertical change or any horizontal change indicates a defective nozzle. Review Illustrations 9 through 12.

Illustration 9	g00319183
A Good Nozzle That Can Be Used Again

Illustration 10	g00319184
Discharge of an Orifice with a Restriction

Replace this fuel injection nozzle.

Illustration 11	g00319185
Discharge of an Orifice with a Horizontal Distortion

Replace this fuel injection nozzle.

Illustration 12	g00319186
Discharge of an Orifice with a Vertical Distortion

Replace this fuel injection nozzle.

Leakage Test for Air Purge Screw

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Illustration 13	g00314154
Fuel Injection Nozzle (19) Air purge screw and seal.

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NOTICE
Do not tighten the air purge screw more than the listed torque amounts. The air purge screw or the seal can be damaged.

1. Install air purge screw and seal (19) into the fuel injection nozzle.

   Note: Refer to Specifications, "Fuel Injection Nozzles and Adapters" for information on torques.

2. Point the tip of the fuel injection nozzle into the extension and toward the fuel collector.

3. Close on/off valve (10) .

4. Open gauge protector valve (7) and pump isolator valve (11) .

5. Pump the tester until the fuel injection nozzle fills with test fluid and the pressure gauge shows 12800 to 14800 kPa (1850 to 2150 psi).

   Note: To attain a pressure of 12800 to 14800 kPa (1850 to 2150 psi), you might need to pump the tester for 15 strokes or for 20 strokes.

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   Table 4

   Specification for Air Purge Screw

   No leakage can occur between the air purge screw and the fuel injector nozzle's body.

6. If leakage occurs, follow this procedure:

   1. Replace the seal (15) .

   2. Inspect the seal face of the air purge screw for damage. Replace the air purge screw, if necessary.

   3. Retest the fuel injection nozzle. If leakage still occurs, the complete fuel injection nozzle needs to be replaced.

7. If no leakage occurs, follow this procedure:

   1. Continue using the same fuel injection nozzle, but replace the seal.
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   Illustration 14	g00319236
   Installing a Carbon Dam (14) Carbon dam. (15) Seal. (17) 6V-4979 Carbon Seal Installation Tool .

   2. Also, install a new carbon dam in the nozzle's groove with a 6V-4979 Carbon Seal Tool (17) .

Fuel Injection Lines

Fuel from the Fuel Injection Pumps to the Fuel Injection Nozzles

Fuel from the fuel injection pumps flows to the fuel injection nozzle through fuel injection lines.

When fuel injection lines are disconnected, always place caps on the end and plugs on the end. This will keep the dirt out of the fuel injection lines. When fuel injection lines are installed, ensure that all clamps and all dampers are returned to original positions.

The nuts that connect a fuel injection line to both the fuel injection nozzle and the fuel injection pump must be tightened to the correct torque.

If the nuts are not tightened to the proper torque, the following problems may occur:

• If the nut is loose, fuel will leak from the connection.

• If the nut is too tight, the inside diameter of the line will become smaller. This causes a restriction to the fuel flow in the fuel line.

Use a torque wrench and a 5P-0144 Fuel Line Socket to tighten the fuel injection line nut to a torque of 41 ± 7 N·m (30 ± 5 lb ft).

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Fuel injection lines that are bent, damaged, or rubbing against surfaces can leak and cause a fire. Replace any lines that are bent, or damaged when tightened to the correct torque. Correct or replace any lines that are rubbing when tightened to the correct torque.

Checking the Plunger and Lifter of an Injection Pump

Note: If the pump plunger is worn, good contact will not occur. A pump plunger must be replaced if the pump plunger is damaged. A lifter must also be replaced if the lifter is worn. There are no different sizes of spacers that are available so you can adjust the timing dimension of the fuel injection pumps. Since there is no possible adjustment to the timing dimension, no off-engine adjustment procedure for the engine lifter setting procedure is available.

If the pump plunger on the fuel injector is worn, the lifter may also be worn. If either of these conditions exists, good contact will not be possible. Replace the lifters soon after you see wear on the pump plunger. Also, replace lifters that show any signs of wear.

Illustration 15	g00319239
Wear Between the Lifter and the Pump Plunger (1) The contact surface of a new pump plunger and surface of a new lifter (2) The contact surface of a pump plunger with considerable wear and surface of lifter with considerable wear (3) Fast wear due to the new end of a pump plunger with poor contact against worn lifter

A fuel injection pump can send a good fuel flow, yet this fuel injection pump may not be a good pump. Wear on the bottom end of the pump plunger causes slow timing. When you test a used fuel injection pump with a long life, use a micrometer to measure the length of the pump plunger.

If the length of the pump plunger is shorter than the minimum, specified length, replace the fuel injection pump. Any amount that is below the specified length indicates that the pump plunger is worn. See Table 5 for more information on the Fuel Pump Plunger.

Table 5

Specifications for Fuel Pump Plunger
Length for new fuel pump plunger	73.886 ± 0.013 mm (2.9089 ± .0005 inch)
Minimum length for worn fuel pump plunger	73.873 mm (2.9084 inch)

Also, look for wear at the top of the pump plunger. Check the operation according to the instructions in Testing and Adjusting, "Fuel Injection Test Bench".

Removal and Installation of Fuel Injection Pumps

Table 6

Required Parts
Part Number	Part Name	Quantity
8T-5287	Wrench	1
8S-2244	Pump Extractor	1
6V-4186	Fuel Pump Timing Pin	1

Removal of Fuel Injection Pumps

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NOTICE
Before any parts are removed from the fuel injection pump housing, thoroughly clean all dirt from the housing. Dirt that gets inside the pump housing will cause much damage.

Note: The fuel rack must be in the center position before the fuel injection pumps can be removed.

Illustration 16	g00319266
Fuel Injection Pump Housing (1) Timing pin cover.

1. Remove timing pin cover (1) from the side of the fuel injection pump housing.

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Illustration 17	g00319267
(2) Timing pin.

2. Move the governor lever to the FUEL-OFF position. Install timing pin (2) in the rack centering hole.

3. With timing pin (2) in position, move the governor lever to the HIGH IDLE position.

   The fuel rack will then move until the edge of the rack's groove contacts the timing pin. Now, the fuel rack is positioned in the center.

4. Fasten the governor lever to the HIGH IDLE position.

5. Remove the fuel injection line from the fuel injection pump.

6. Place the 8T-5287 Wrench into the spline of the bushing that holds the fuel injection pump inside the housing. Remove the bushing.

7. Install the 8S-2244 Pump Extractor on the threads of the fuel injection pump.

8. Carefully pull the fuel injection pump from the engine's bore. Pull the fuel injection pump straight up from the engine's bore.

Be careful when you disassemble a fuel injection pump. Do not damage the pump plunger's surface. The pump plunger and barrel assembly are made as a set.

Do not interchange the pump plunger of one barrel assembly with one from another pump plunger. The parts of these sets are not interchangeable. If any part of the fuel injection pump assembly is worn, install a new, complete fuel injection pump assembly.

Also, be careful in putting the pump plunger into the barrel's bore. When you remove the fuel injection pumps and you remove the fuel pump spacers from the fuel injection pump assembly, keep the parts together. Ensure that each component can be returned to that component's original location in the housing assembly.

Installation of Fuel Injection Pumps

Note: The fuel rack must be positioned in the very center before you can correctly install a fuel injection pump.

1. Ensure that the fuel rack is center of the rack's travel.

2. Install the 8S-2244 Pump Extractor on the threads of the fuel injection pump.

3. Ensure that the pump's lifter is installed at the bottom of the lifter's travel.

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Illustration 18	g00319563
Fuel Pump Installation (3) 8S-2244 Extractor. (4) Groove on barrel. (5) Fourth tooth of gear segment.

4. Align the groove on barrel (4) with the middle tooth of gear segment. This middle tooth is the fourth tooth of gear segment (5) .

5. Look into the bore for the fuel injection pump, and locate both dowels.

   There is a dowel in the lifter. On the opposite side of the bore, there is another dowel.

6. Align the groove on barrel (4) with the larger dowel in the fuel injection pump housing. At the same time, position the slot on the opposite side of the gear teeth on the sector gear.

   This should be in alignment with the smaller dowel inside the lifter.

7. Install the fuel injection pump straight down into the bore.

8. Push down on extractor (3). Use hand force only, and install the O-ring and the bushing. The bushing holds the fuel injection pump inside the pump housing.

   If the pump is in the correct position, the bushing will turn clockwise toward the threads of the fuel injection housing. The bushing should be turned with the fingers until the bushing is flush with the top of the housing.

9. After the bushing is correctly installed, tighten the bushing to 163 ± 14 N·m (120 ± 10 lb ft).

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NOTICE
The bushing must be tightened to the correct torque. Damage to the housing will be the result if the bushing is too tight. If the bushing is not tight enough, the pump will have leakage.

10. Install the fuel injection line to the fuel injection pump. Tighten the lines to a torque of 41 ± 7 N·m (30 ± 5 lb ft).

11. Remove timing pin (2), and install timing pin cover (1) .

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    NOTICE
    If one or more of the fuel injection pumps have been installed wrong, it is possible for the engine to run out of control when started. When any of the fuel injection pumps have been removed and installed, take precautions (steps) that follow to stop the engine if it starts to overspeed (run out of control).

    1. Remove the air cleaner pipe from the turbocharger. Ensure that you leave the air inlet for the turbocharger open.

    2. Set the governor to a low idle.
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    Illustration 19	g00319604

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    Be careful when placing the steel plate against the opening on the turbocharger air inlet. To avoid crushed fingers, do not position fingers between the steel plate and the opening on the turbocharger air inlet. Due to excessive suction, the plate can be forcefully pulled against the opening on the turbocharger air inlet.

    3. Start the engine.

       If the engine starts to run out of control (overspeed), carefully place a steel plate over the air inlet opening. This stops the engine.

Finding the Top Center Position For No. 1 Piston

Table 7

Tools Needed Quantity
Part Number	Part Name	Quantity
5P-7307	Engine Turning Tool	1

The starting point for all timing procedures is with the No. 1 piston at the top center position on the compression stroke.

Note: The engine is seen from the flywheel end when the direction of the crankshaft rotation is given.

1. Remove the starting motor.

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Illustration 20	g00319605
(1) 5P-7306 Shaft Housing. (2) 5P-7305 Gear Timing Bolt. (3) Timing bolt.

2. Install the tools in Illustration 20, as shown.

   Note: If the flywheel is turned beyond the point of engagement, the flywheel must be turned in the direction that is opposite of normal engine rotation. Turn the flywheel by approximately 30 degrees. Then, turn the flywheel in the direction of normal engine rotation until the timing bolt engages with the threaded hole. When the No. 1 piston is at the top center position, this procedure will remove the play from the gears.

3. Remove the valve cover.

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Illustration 21	g00319609
Removed Valve Cover (4) Rocker arms.

4. Rotate the crankshaft clockwise by approximately 30 degrees.

   This step removes the free play from the timing gears after the No 1 piston is put at the top center position.

5. Remove the plug from the timing hole in the flywheel housing.

6. Rotate the crankshaft until a 3/8-16 NC bolt that is 50.8 mm (2.00 inch) long can be rotated into the flywheel through the timing hole in the flywheel housing. The No. 1 piston is now at the top center position.

   Note: If the crankshaft turns beyond the top center, repeat Step 4 and Step 5.

   Now, No. 1 piston is at the top center position.

7. If No. 1 piston is on the compression stroke, all of the valves should be closed.

   You can move rocker arms (4) up and down with your hand.

If No. 1 piston is not on the compression stroke, follow these steps:

1. Remove the timing bolt.

2. Rotate the crankshaft counterclockwise by 360 degrees.

3. Install the timing bolt.

   The No. 1 piston is now at the top center position on the compression stroke.

Checking Engine Timing with 8T-5300 Engine Timing Indicator Group and 8T-5301 Diesel Engine Timing Adapter Group

Table 8

Required Tools
Part Number	Part Name	Quantity
8T-5300	Engine Timing Indicator Group	1
8T-5301	Diesel Engine Timing Adapter Group	1

Illustration 22	g00319643
8T-5300 Engine Timing Indicator Group (1) 8T-5250 Engine Timing Indicator (2) 5P-7366 Power Cable (3) 6V-2197 Magnetic Transducer (4) 5P-7362 Cable (5) 6V-2199 Transducer Adapter and 6V-3093 Transducer Adapter (6) 8K-4644 Fuse

The 8T-5300 Engine Timing Indicator Group must be used with the 8T-5301 Diesel Engine Timing Adapter Group.

Illustration 23	g00319663
8T-5301 Diesel Engine Timing Adapter Group (7) 5P-7437 Adapter (8) 6V-2198 Cable (9) 5P-7436 Adapter (10) 6V-7910 Transducer (11) 5P-7435 Adapter (12) 6V-3016 Washer

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A high pressure fuel line must be disconnected. To avoid personal injury or fire from fuel spray, the engine must be stopped before the fuel line is disconnected.

When you check for the dynamic timing on an engine without a mechanical advance, Caterpillar Inc. recommends the recording of the calculations for the dynamic timing onto paper. Then, the service person can create a graph of the dynamic advance.

Note: Order one Special Instruction, SEHS8140. Worksheets are available in pads of 50. See Special Instruction, SEHS8580 for information on calculating the timing curve.

Note: For all engines that are regulated for emission control, use the dynamic timing at 1000 rpm to measure the static fuel injection timing. Also, use the dynamic timing at 1000 rpm to set the static fuel injection timing. Do not use the timing pin method for this measurement or for this setting.

After the timing values are calculated and the timing values are plotted, the dynamic timing should be checked with the 8T-5300 Engine Timing Indicator Group. Follow these steps:

1. Operate the engine from 1000 rpm (base rpm) to high idle.

2. Continue running the engine now from high idle to 1000 rpm (base rpm).

   Unstable readings often appear below 1000 rpm.

3. Record the dynamic timing at each 100 rpm and at the specified rpm during acceleration and during deceleration.

4. Finally, plot the results onto the worksheet. Review the plotted values.

Use Special Instruction, SEHS8580 to see the correct specifications for calculating the timing curve.

You can find these specifications in three places:

• The Operating Instructions inside the lid of the 8T-5300 Engine Timing Indicator Group

• The Special Instruction, SEHS8580

• The Engine Information Plate for the performance specification number

The performance specification number can be used to refer to the TMI. Here, you will find the correct timing specifications to use.

Procedure for Timing Check

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A high pressure fuel line must be disconnected. To avoid personal injury or fire from fuel spray, the engine must be stopped before the fuel line is disconnected.

Illustration 24	g00319821
Transducer in Position (10) Injection transducer. (13) Fuel injection line for No. 1 cylinder.

1. Loosen all fuel injection line clamps that hold No. 1 fuel injection line. Disconnect fuel injection line (13) at the fuel injection pump.

2. Slide the nut upward. Attach the 5P-7436 Adapter (9).

3. Tighten 5P-7436 Adapter (9) onto the pump bonnet. Turn adapter (9) onto the pump bonnet. Continue until the top of the bonnet's threads lines up with the bottom of the opening in adapter (9) .

4. Attach 5P-7435 Adapter (11) onto injection transducer (10). Then, connect 5P-7435 Adapter (11) in the opening of 5P-7436 Adapter (9) .

5. Place fuel injection line (13) on top of 5P-7435 Tee Adapter (11). Install 5P-7437 Adapter (7). Tighten the adapter (7) to a torque of no more than 40 N·m (30 lb ft).

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Illustration 25	g00319823
Transducer in Position (3) Top center magnetic transducer. (5) Transducer adapter.

6. Remove the plug from the flywheel housing. Install transducer adapters (5) into the hole that is remaining from the plug's removal. Tighten transducer adapters (5) only by a small amount.

7. Push top center magnetic transducer (3) into transducer adapters (5) until this adapter contacts the flywheel.

8. Pull the top center magnetic transducer (3) out of the transducer adapter by 1.6 mm (.063 inch). Then, lightly tighten the knurled locknut.

9. Connect the cables from top center magnetic transducer (3) to 8T-5250 Engine Timing Indicator (1). Calibrate the indicator, and make any necessary adjustments.

   Note: See Special Instruction, SEHS8580 for more information on the calibration procedure.

10. Start the engine, and allow the engine to reach operating temperature. Then, run the engine at approximately one half throttle for eight to ten minutes. After this amount of time, measure the engine's timing.

11. Run the engine at increments of 100 rpm between 1000 rpm (base rpm) and high idle. Record the readings for engine timing, and then plot these readings onto a graph.

    Note: Use smaller increments to pinpoint the times when the timing advance starts. You can also use smaller increments to pinpoint the times when the timing advance stops.

    The engine's timing is set under the following conditions:

    • The readings for the timing indicator are within ±2.5 degrees of the timing that was calculated on the graph.

    • The angle of the change is approximately the same amount.

    Therefore, the engine's timing should be operating correctly.

    A timing adjustment may be needed under the following conditions:

    • The readings are NOT within ±2.5 degrees of the timing that was calculated on the graph.

    • The angle of the change is NOT smooth through the speed range.

    Refer to "Timing Adjustment by Timing Pin Method" for the static adjustment of the drive for the fuel injection pump.

If the automatic timing advance is not correct, repair the automatic timing advance unit, or replace the automatic timing advance unit.

Note: If you used the 8T-5250 Engine Timing Indicator (1) to set the engine timing, the timing pin may not fit into the slot in the fuel pump crankshaft. The flywheel will be at the top center position. (See "Finding the Top Center Position for No. 1 Piston".) This is a common result of using the dynamic timing indicator to set the timing instead of using the less accurate timing pin method.

Timing Adjustment by Timing Pin Method with 8T-5300 Engine Timing Indicator

Note: For all engines that are regulated for emission control, use the dynamic timing at 1000 rpm to measure the static fuel injection timing. Also, use the dynamic timing at 1000 rpm to set the static fuel injection timing. Do not use the timing pin method for this measurement or for this setting.

Table 9

Required Tools
Part Number	Part Name	Quantity
8S-2264	Pump Impeller Puller	1
1B-3680	Bolt (1)	2
4B-5271	Washer	2
8B-7560	Step Plate	1
6F-7030	Bolt (2)	2
6V-4186	Fuel Pump Timing Pin	1
6V-6176	Adapter	1

( 1 )	The bolt (3/8-24 NF) is 95.3 mm (3.75 inch) long.
( 2 )	The bolt (3/8-24 NF) is 25.4 mm (1.00 inch) long.

1. Move the No. 1 piston to the top center position on the compression stroke. Remove the timing bolt.

   Note: Refer to "Finding the Top Center Position for No. 1 Piston".

2. Rotate the crankcase counterclockwise by 30 degrees.

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Illustration 26	g00319826
Timing Pin Cover (1) Timing pin cover. (2) Cover for timing gear. (3) Nut.

3. Remove timing pin cover (1) from the side of the fuel injection pump housing.

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Illustration 27	g00319828
Installed Fuel Pump Timing Pin (4) 6V-4186 Fuel Pump Timing Pin .

4. Install 6V-4186 Fuel Pump Timing Pin (4) in the fuel injection pump housing. See Illustration 27.

5. Slowly rotate the crankshaft counterclockwise until fuel pump timing pin (4) fits into the slot inside the fuel pump camshaft.

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NOTICE
Too much pressure on the timing pin can damage the fuel injection pump camshaft or the timing pin.

6. Place the timing bolt into the timing hole in the flywheel housing.

7. Slowly move the crankshaft counterclockwise until the fuel pump camshaft fits tightly against the timing pin. View the engine from the flywheel end during this procedure.

   This removes the gear clearance from the drive train.

   1. If the timing bolt can be installed in the flywheel and the timing pin can be installed in the fuel pump camshaft, the timing is correct.

   2. If either the timing bolt or the timing pin can NOT be installed, follow Steps 8 through 18.

8. Remove nuts (3) and timing pin cover (2) from the timing gear housing.

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Illustration 28	g00319830
Timing Gear for Fuel Injection Pump (5) Bolt.

9. Loosen bolt (5) that connects the timing gear to the fuel pump camshaft. Turn bolt (5) counterclockwise for three turns.

10. Install the 8S-2264 Pump Impeller Puller and loosen the timing gear from the fuel pump camshaft.

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Illustration 29	g00319832
Installed Puller Tools (6) 8S-2264 Pump Impeller Puller (7) 8B-7560 Step Plate (8) 1B-3680 Bolt (9) 4B-5271 Washer

11. Rotate the flywheel clockwise to 60 degrees before No. 1 piston reaches the top center position.

12. Tighten bolt (5) finger tight. Ensure that fuel pump timing pin (4) fits inside the groove in the fuel pump camshaft.

13. Slowly rotate the crankshaft counterclockwise until the timing bolt can be installed in the flywheel.

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Illustration 30	g00319834
Installed Adapter on the Timing Gear (10) 4C-9874 Spanner Wrench .

14. Install 4C-9874 Spanner Wrench (10) onto the timing gear.

15. Maintain a torque of 60 to 70 N·m (45 to 50 lb ft) on spanner wrench (10) in a clockwise direction, and tighten bolt (5) that retains the timing gear to 270 ± 25 N·m (200 ± 20 lb ft).

16. Remove the timing bolt from the flywheel and remove fuel pump timing pin (4) from the fuel pump camshaft.

17. Rotate the crankshaft counterclockwise for two revolutions.

    1. If the timing bolt can be installed in the flywheel and the timing pin can be installed in the fuel pump camshaft, the timing is correct.

    2. If either the timing bolt or the timing pin can NOT be installed, repeat Steps 8 through 17.

18. Use the 8T-5300 Engine Timing Indicator Group to verify the change to the engine's timing.

Governor Adjustment for Fuel Ratio Control Linkage

Table 10

Required Tools
Part Number	Part Name	Quantity
6V-4186	Fuel Pump Timing Pin	1
6V-2105	Rack Adjusting Tool	1
6V-2017	Governor Adjustment Tool	1
0S-1614	Bolt	1
9S-0229	Indicator Contact Point	1
5P-4814	Collet Clamp	1
6V-3075	Dial Indicator	1
6V-7941	Spring Compressor	1
6V-2014	Bracket	1

The governor adjustment for the fuel ratio control linkage can be completed with the fuel injection pump and the governor on the engine or with the fuel injection pump and the governor off the engine.

Illustration 31	g00319835
Fuel Injection Pump and Governor (1) Cover.

1. Remove cover (1) from the side of the fuel injection pump housing.

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Illustration 32	g00319836
Installed Bracket Assembly (2) 5P-4814 Collet Clamp. (3) 6V-2014 Bracket .

2. Install 5P-4814 Collet Clamp (2) onto 6V-2014 Bracket (3).

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Illustration 33	g00319837
Fuel Injection Pump and Governor with Removed Cover (4) Slot on fuel rack.

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Illustration 34	g00319838
Bracket Assembly (5) Lever. (6) Shaft.

3. Install bracket assembly (3) onto the fuel pump housing.

   Lever (5) on bracket assembly (3) must be inserted into slot (4) on the fuel rack. Push up on the bracket assembly (3) while you tighten the bolts.

   After bracket assembly (3) is tightened to the fuel pump housing, shaft (6) must have an axial movement. Axial movement alternates between clockwise movement and counterclockwise movement. If there is no axial movement of the shaft, follow these steps:

   1. Ensure that lever (5) is securely inserted into the slot on the fuel rack.

   2. Ensure that lever (5) is not bent.

   3. Ensure that the bracket assembly is installed correctly.

   4. Ensure that lever (5) is at a right angle (perpendicular) to the mounting face of the bracket assembly.

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Illustration 35	g00319839
Installed Dial Indicator (7) 6V-3075 Dial Indicator

4. Connect the 9S-0229 Indicator Contact Point to 6V-3075 Dial Indicator (7), and install the dial indicator into 5P-4814 Collet Clamp (2) .

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Illustration 36	g00319925
Governor (8) Fuel air ratio control.

5. Remove fuel air ratio control (8) from the rear of the governor housing.

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Illustration 37	g00321104
Rear of Governor Housing (9) Plug.

6. Remove plug (9) from the rear of the governor housing.

7. Move the governor control lever to the FUEL-OFF position.

   Note: Rotate the governor shaft clockwise.

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Illustration 38	g00319943
Installed Fuel Pump Timing Pin (10) 6V-4186 Fuel Pump Timing Pin .

8. Install 6V-4186 Fuel Pump Timing Pin (10) into the hole in the bracket assembly.

   Push in the fuel pump timing pin (10) until the timing pin contacts the fuel rack. Then, hold the fuel pump timing pin gently against the fuel rack for Steps 9 and 10.

   If too much force is used to hold the fuel pump timing pin, the fuel rack can stick. This causes an incorrect zero reading.

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Illustration 39	g00319963
Using the 6V-7942 Hook (11) 6V-7942 Hook .

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Illustration 40	g00320023
Cutaway View of Governor (11) 6V-7942 Hook. (12) Collar.

9. Hold the governor control lever in the HIGH IDLE position.

   Note: Rotate the governor shaft counterclockwise.

10. Place the fuel rack into zero position.

    1. Insert 6V-7942 Hook (11) into the hole that is left from the removal of plug (9) .

    2. Engage the end of 6V-7942 Hook (11) with collar (12) .

    3. Pull these two components toward the rear of the governor housing until the collar stops moving.

       This ensures that the fuel rack stops against fuel pump timing pin (10). The rack will then be in zero position.

11. Complete these final steps for removing the timing pin:

    1. With hook (11) that is pulled toward the rear of the governor housing, loosen collet (2) .

    2. Then, adjust the revolution counter on the dial indicator to zero.

    3. Tighten collet (2) enough to hold the indicator in this position.

    4. Proceed to move the indicator's dial to zero.

12. Remove fuel pump timing pin (10) .

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Illustration 41	g00320183
6V-7941 Spring Compressor (13) Rod. (14) Knob.

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Illustration 42	g00320203
Installed Compressor Assembly (15) 6V-7941 Spring Compressor .

13. Turn rod (13) out of 6V-7941 Spring Compressor (15) until knob (14) is 25.4 mm (1.00 inch) from the compressor body. Install the 6V-7941 Spring Compressor (15) into the hole that is left from the removal of plug (9) .

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Illustration 43	g00320223
Installed Governor Adjusting Tool (16) 6V-2017 Governor Adjustment Tool .

14. Move the governor control lever to the FUEL-OFF position.

    1. Use two OS-1614 Bolts to install 6V-2017 Governor Adjustment Tool (16) .

    2. Ensure that the end of the tool is behind the governor linkage.

    3. Also, ensure that the flange is completely against the governor housing. Remember that the filter screen may need to be removed.

       Note: If you expect to change the setting, install the outer part of 6V-2105 Rack Adjusting Tool. Install this tool along the left side of the 6V-2017 Governor Adjustment Tool (16) .

15. Move the governor control lever to the FULL LOAD position. Then, hold the governor control lever in this position.

16. Turn the spring clockwise until the indicator hand stops moving. This is the Static Fuel Ratio Control Lever Setting.

17. Now, slowly turn the rod counterclockwise until the indicator hands stop moving. This is the Static Fuel Ratio Control Lever Setting.

    Note: There will be a small, initial amount of movement by the indicator hands. Then, the indicator hands will stop moving while the rod is turned out for another 1 1/2 turns. Now, the indicator hands will begin to move again. The indicator hands will follow the turning of the rod until the setting is reached. Remember to turn the rod slowly so the rack can follow the governor components.

18. Compare the reading on the dial indicator to the correct fuel ratio lever setting in the TMI.
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    Illustration 44	g00320243
    Governor Linkage Adjustment (17) 6V-2105 Rack Adjusting Tool .

    1. If the fuel ratio control setting is not correct, use 6V-2105 Rack Adjusting Tool (17) to loosen the locknut (19) .
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    Illustration 45	g00320264
    Adjustment Screw for Governor (18) Adjustment screw. (19) Locknut.

    2. Turn adjustment screw (18) clockwise. This decreases the amount of fuel that is possible. This also allows less fuel rack travel at the limited rack position.

       Note: One revolution of the adjustment screw will change the setting by approximately 0.79 mm (.031 inch). Also, remember that the dial indicator hands will not follow the movement of the adjustment screw. You need to repeat Steps 15 through 18 until the correct setting is obtained.

Fuel Air Ratio Control and Governor Check

Table 11

Required Tools
Part Number	Part Name	Quantity
2W-9161	Manual Shutoff	1
6V-4186	Fuel Pump Timing Pin	1
6V-6070	Governor Adjusting Tool Group	1
0S-1614	Bolt	1
9S-0229	Indicator Contact Point	1
9U-7400	Multitach	1
FT-1906	Air Test Kit	1
8T-1000	Electronic Position Indicator	1
4N-5656	Governor Cover	1

Note: The governor seals do not need to be cut or removed for the procedures that follow. For more information on the tooling, watch Video Tape, SEVV9173 and Special Instruction, SEHS8463. This Special Instruction is available only on microfiche.

1. Install the rack position indicator in order to measure the fuel rack's movement. See Steps 1 through 5 in the "Fuel Setting Procedure" for the correct installation of the tooling.

2. Turn the ignition key to "ON". This activates the shutoff solenoid. DO NOT START THE ENGINE AT THIS TIME.

3. Move the governor control linkage to the full FUEL-ON position. Hold the governor control linkage in this position, or fasten the control linkage in this position.

4. Install the 6V-4186 Fuel Pump Timing Pin in the hole for rack's zeroing pin inside the pump housing.

5. With the governor control lever in the full FUEL-OFF position, use a 1N-9954 Lever to slowly move the manual shutoff shaft, if equipped. Move this manual shutoff shaft to the FUEL-OFF position. This moves in a counterclockwise direction.

   Ensure that the 6V-4186 Fuel Pump Timing Pin drops into the slot in the fuel rack. Also, ensure that the pin engages with the slot in the fuel rack.

6. Release the manual shutoff shaft and the 8T-1000 Electronic Position Indicator. Press the zero button.

7. Remove the 6V-4186 Fuel Pump Timing Pin, and watch the movement.

   The electronic position indicator should display a positive reading in the "FUEL ON" direction.

   Note: If no movement occurs, repeat Steps 4, 5, and 6.

8. Release the governor control shaft and the governor control linkage.

9. Remove the air line from the engine. Put plugs over the opening. This keeps dirt out of the system.

10. Start the engine, and allow the engine to run for a minimum of five minutes. This warm-up time is required for the following reasons:
    • The governor gets enough time to attain normal operating temperature.

    • The engine gets enough time to attain normal operating temperature.

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Personal injury can result from rotating and moving parts. Moving fan blades and moving parts will throw or cut any object or tool that falls or is pushed into them. Ensure that no one is working on, underneath or close to the machine before starting the engine. Ensure the area is free of personnel.

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Illustration 46	g00320303
FT-1906 Air Test Kit (1) 8L-6557 Flared Connector (2) 5P-4405 Air Brake Connector (two are necessary) (3) 5P-6011 Tube (4) 5P-4476 Air Brake Connector (5) 6K-5741 Drain Valve (6) 5P-4459 Air Brake Elbow (7) 7B-0192 Connector (8) 3B-6768 Reducer Bushing (9) 6V-7775 Air Pressure Gauge (10) 6N-3169 Hose Assembly (11) 6V-6757 Pipe Elbow (12) ID Flexible Tubing that is 6.35 mm (.2500 inch) and 1.2 m (4 ft) long (13) Air pressure bulb (Baumamometer No. 1890 or equivalent)

11. Check the leakdown rate of the fuel air ratio control with the engine at low idle. Follow these steps:

    1. Connect the following items to the fitting that was left from the removal of the air line:
       • Pressure gauge

       • Shutoff valve

       • Pressure regulator

       • Air supply

    2. Apply 70 kPa (10 psi) of air pressure to the fuel air ratio control.

    3. Turn off the shutoff valve, and check the leakdown rate.

       Note: A leakdown rate of 20 kPa (3 psi) within 30 seconds is acceptable.

    4. If leakage is more than 20 kPa (3 psi) within 30 seconds, the fuel air ratio control needs to be repaired before Steps 14 through 16 are completed.

    5. Apply 70 kPa (10 psi) of air pressure on the fuel air ratio control for Step 12.

       Note: Step 11 also activates the fuel air ratio control for Step 12.

12. While the engine is operating at low idle, rapidly move the governor control shaft to the FUEL-ON position. Then, read the measurement on the 8T-1000 Electronic Position Indicator .

13. Press the "MAX" on the position indicator and then read the dynamic fuel ratio control setting. Record the reading, and repeat this step several times.

    Note: The fuel air ratio control is activated, and the maximum reading is the dynamic full torque setting of the engine. This setting is 0.5 mm (.02 inch) greater than the static full torque setting. The static full torque setting appears on the Engine Information Plate for later engines. This information can also be found in the TMI.

    Note: The fuel air ratio control activates at start-up for engines with a fuel air ratio control that is out of adjustment. At this time, the reading of the 8T-1000 Electronic Position Indicator can be the dynamic full torque setting for Step 17.

14. Release all the air pressure from the fuel air ratio control.

15. While the engine is operating at 900 rpm, rapidly move the governor control shaft to the FUEL-ON position. Then, read the measurement on the 8T-1000 Electronic Position Indicator .

16. Press the "MAX" on the indicator, and then read the dynamic fuel ratio control setting. Record the reading, and repeat this step several times.

    Note: An adjustment is not needed if the dynamic fuel ratio setting is within 0.25 mm (.010 inch) of the specifications in either of the following references:

    • The Engine Information Plate for later engines

    • TMI

    For the adjustment of the control, see the "Fuel Ratio Control Adjustment" topic.

17. Observe these steps to check the inlet air pressure for full torque rack travel:

    1. Connect the following items to the fitting that was left from the removal of the air line:
       • Pressure gauge

       • Pressure regulator

       • Air supply

    2. Apply 25 kPa (4 psi) of air pressure to the fuel air ratio control.

    3. Run the engine at 900 rpm. Rapidly move the governor control shaft to the full FUEL-ON position. Record the maximum reading on the indicator.

    4. Repeat this process several times. With each repetition, increase the air pressure by 5 kPa (.5 psi).

    5. Record the first air pressure setting that registers the full torque rack travel.

       Note: Remember that the full torque rack travel was calculated in Step 13.

    6. This is the inlet air pressure that moves the fuel air ratio control out of the rack control position. This pressure provides the dynamic full torque rack travel.

Fuel Ratio Control Adjustment

Table 12

Required Tools
Part Number	Part Name	Quantity
2W-9161	Manual Shutoff	1
6V-4186	Fuel Pump Timing Pin	1
6V-6070	Governor Adjusting Tool Group	1

Note: Before the governor seals are removed or the governor seals are severed, check the "Fuel Ratio Control and Governor Check" in order to ensure that an adjustment is needed.

1. See either of the following references for the correct specification of the dynamic fuel ratio setting before you make an adjustment:
   • The Engine Information Plate for later engines

   • TMI

2. Install the zero rack position indicator group, and zero the rack position indicator.

   Note: See the "Fuel Ratio Control and Governor Check" for more information regarding this procedure.

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Illustration 47	g00320407
Earlier Fuel Air Ratio Control (1) Nut (valve extension). (2) Retainer. (3) Stop. (4) Nut. (5) Valve extension.

3. Remove the cover from the fuel ratio control valve.

   Note: For earlier engines, the completion of Step 4 is necessary to ensure that stop (3) does not contact retainer (2). Later engines do not contain stop (3) and nut (4). Do not add these parts when you repair the fuel air ratio control.

4. Loosen nut (4), and turn stop (3) clockwise until stop (3) contacts the shoulder on retainer (2). Next, turn the stop (3) counterclockwise for two complete turns. Tighten nut (4) .

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Illustration 48	g00367447
Later Fuel Air Ratio Control (1) Nut (valve extension). (5) Valve extension.

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Personal injury can result from rotating and moving parts. Moving fan blades and moving parts will throw or cut any object or tool that falls or is pushed into them. Ensure that no one is working on, underneath or close to the machine before starting the engine. Ensure the area is free of personnel.

5. Start the engine, and allow the engine to run for a minimum of five minutes. This warm-up time is required for the following reasons:
   • The governor gets enough time to attain normal operating temperature.

   • The engine gets enough time to attain normal operating temperature.

6. Activate the fuel air ratio control by pushing in on valve extension (5) .

7. Hold retainer (2) in position, and loosen nut (1). This prevents the fuel ratio control diaphragm from turning when you loosen nut (1) .

   Note: Use the same procedure to tighten this nut.

8. Turn valve extension (5) in order to attain the correct setting. A clockwise movement provides a more positive setting.

   Note: A counterclockwise movement provides a more negative setting.

   Several adjustments of valve extension (5) may be needed to meet the specifications.

9. After each adjustment is made, check the dynamic fuel ratio control setting:

   1. Operate the engine at 900 rpm, and rapidly move the governor control shaft to the FUEL-ON position.

   2. Carefully read the dial indicator. This reading will be at the maximum for only a moment. Record the reading on the indicator.

      Note: If the correct dynamic fuel ratio control setting can NOT be made with this adjustment, check the internal governor linkage for another possible adjustment. Check the fuel ratio control linkage for repair and for replacement.

10. After the correct adjustment has been made and while you are holding retainer (2) in position, tighten nut (1). Also, check the fuel ratio control setting again.

11. Install the gasket and the cover on the fuel ratio control. Then, install the cover to a torque of 9 ± 3 N·m (7 ± 2 lb ft).

12. Apply 70 kPa (10 psi) of air pressure to the fuel air ratio control at the fitting. This will fully extend the fuel air ratio control so the dynamic full torque can be attained.

13. Check the dynamic full torque setting:

    1. Operate the engine at 900 rpm.

    2. Rapidly move the governor control shaft to the full FUEL-ON position.

    3. Read the maximum measurement that is displayed on the dial indicator.

       Note: If the dynamic full torque setting can NOT be reached, the fuel air ratio control may need to be repaired or replaced.

14. Stop the engine.

15. Install the wire and the seal onto the fuel air ratio control.

16. Install the air line onto the engine.

17. Remove the tooling for the rack position indicator.

Fuel Setting Procedure

Table 13

Required Tools
Part Number	Part Name	Quantity
6V-6070	Governor Adjusting Tool Group	1
8T-0500	Continuity Tester	1

The static fuel setting can be determined with the fuel injection pump on the engine or with the fuel injection pump off the engine. For more information, see Special Instruction, SEHS8024.

Illustration 49	g00319835
Fuel Injection Pump and Governor (1) Cover.

1. Remove cover (1) from the side of the fuel injection pump housing.

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Illustration 50	g00319836
Installed Bracket Assembly (2) 5P-4814 Collet Clamp. (3) 6V-2014 Bracket .

2. Install 5P-4814 Collet Clamp (2) onto 6V-2014 Bracket (3) .

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Illustration 51	g00319837
Removed Cover (4) Slot on the fuel rack.

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Illustration 52	g00319838
6V-2014 Bracket (5) Lever. (6) Shaft.

3. Install 6V-2014 Bracket (3) onto the fuel injection pump housing. Ensure that lever (5) on the bracket assembly fits slot (4) on the fuel rack.

   After the 6V-2014 Bracket (3) is tightened to the fuel injection pump housing, shaft (6) must have axial movement. Axial movement alternates between clockwise movement and counterclockwise movement.

   If there is no axial movement, ensure of these conditions:

   • Lever (5) fits correctly in the slot (4) on the fuel rack.

   • The bracket assembly is attached correctly.

   • Lever (5) is not bent.

   Remember that lever (5) must be at a right angle (perpendicular) to the mounting face of the bracket assembly.

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Illustration 53	g00319839
Installed Dial Indicator (7) 6V-3075 Dial Indicator .

4. 9S-0229 Indicator Contact Point measures 9.7 mm (.38 inch) long. Attach this contact point onto 6V-3075 Dial Indicator (7). Also install the dial indicator in 5P-4814 Collet Clamp (2) .

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Illustration 54	g00319925
Governor (8) Fuel air ratio control.

5. Remove fuel air ratio control (8) from the rear of the governor housing.

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Illustration 55	g00321104
Rear of Governor Housing (9) Plug.

6. Remove plug (9) from the rear of the governor housing.

7. Move the governor control lever to the FUEL-OFF position. This can be done by rotating the governor shaft clockwise.

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Illustration 56	g00319943
Installed Timing Pin (10) 6V-4186 Fuel Pump Timing Pin .

8. Install 6V-4186 Fuel Pump Timing Pin (10) into the hole in the bracket assembly.

   1. Push in fuel pump timing pin (10) until this timing pin contacts the fuel rack.

   2. Hold the fuel pump timing pin (10) gently against the fuel rack for Steps 9 and 11.

      If too much force is used to hold the fuel pump timing pin (10), the fuel rack can stick. This sticking can produce an incorrect zero reading.

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Illustration 57	g00319963
Using 6V-7942 Hook (11) 6V-7942 Hook .

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Illustration 58	g00320023
Cutaway View of Governor (11) 6V-7942 Hook. (12) Collar.

9. Hold the governor control lever in the HIGH IDLE position. Rotate the governor shaft counterclockwise.

10. Insert 6V-7942 Hook (11) into the hole that is left from the removal of plug (9) .

    1. Engage the end of 6V-7942 Hook (11) with collar (12) .

    2. Pull these two components toward the rear of the governor housing until the collar stops moving.

       This ensures that the fuel rack stops against fuel pump timing pin (10). The rack will then be in zero rack position.

11. With hook (11) that is pulled toward the rear of the governor housing, loosen collet (2).

    1. Then, adjust the revolution counter on the dial indicator to zero.

    2. Tighten collet (2) enough to hold the indicator in this position.

    3. Move the indicator's dial to zero.

12. Remove 6V-4186 Fuel Pump Timing Pin (10) .

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Illustration 59	g00320183
6V-7941 Spring Compressor (13) Rod. (14) Knob.

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Illustration 60	g00320203
Installed Compressor Assembly (15) 6V-7941 Spring Compressor.

13. Turn rod (13) out of 6V-7941 Spring Compressor (15) until knob (14) is 25.4 mm (1.00 inch) from the compressor body. Install this assembly into the hole that is left from the removal of plug (9) .

Fuel System Without a Torque Spring

Note: The procedure for checking the fuel setting is different from the procedure for adjusting the fuel setting. Use Steps 1 through 4 to check the fuel setting. Use Steps 6 through 8 to adjust the fuel setting.

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Illustration 61	g00320505
Checking the Static Fuel Setting (16) 8T-0500 Continuity Tester. (17) Rack contact screw. (18) Adjustment screw cover.

1. Fasten the clip end of 8T-0500 Continuity Tester (16) to rack contact screw (17). Connect the other end to an electrical ground.

2. Hold the governor control lever in the FUEL-ON position. Fully rotate the governor control lever in a counterclockwise direction.

3. Turn rod (13) on 6V-7941 Compressor Assembly (15) clockwise until the light in the continuity tester (16) goes out.

   After the light goes out, the hands on the dial indicator will move for an additional 2 mm in the negative direction.

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NOTICE
Do not turn the rod any further inward if the rod begins to tighten. Damage to the governor can occur if the rod is turned further inward.

4. Slowly turn rod (13) counterclockwise until the circuit tester light just turns on. This is the static fuel setting.

   Note: See the TMI for more information on the correct static fuel setting.

   Note: There will be a small, initial amount of movement by the indicator hands. Then, the indicator hands will stop moving while the rod is turned out for another 1 1/2 turns. Now, the indicator hands will begin to move again. The indicator hands will follow the turning of the rod until the setting is reached. Remember to turn the rod slowly so the rack can follow the governor components.

5. If the static fuel setting is not correct, remove adjustment screw cover (18) from the rear of the governor housing.

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Illustration 62	g00320507
Adjustment Screw Cover after Removal (19) Fuel setting screw.

6. Determine the amount that the static fuel setting must change. Use Table 14 for turning measurements. Also, review the following examples carefully.
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   Table 14

   Adjustment Screw Chart
   Amount of Change	Turns of Adjustment Screw
   3.0 mm (.118 inch)	3 3/4
   2.8 mm (.110 inch)	3 1/2
   2.6 mm (.102 inch)	3 1/4
   2.4 mm (.094 inch)	3
   2.2 mm (.087 inch)	2 3/4
   2.0 mm (.079 inch)	2 1/2
   1.8 mm (.071 inch)	2 1/4
   1.6 mm (.063 inch)	2
   1.4 mm (.055 inch)	1 3/4
   1.2 mm (.047 inch)	1 1/2
   1.0 mm (.039 inch)	1 1/4
   .08 mm (.031 inch)	1
   .06 mm ( .024 inch)	3/4
   .04 mm (.016 inch)	1/2
   .02 mm (.008 inch)	1/4

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   Table 15

   Example #1
   Actual Reading	(1.05 mm)
   Desired Reading	(1.25 mm)
   Difference	(0.20 mm)

   Since the desired setting is higher than the actual reading, turn the adjusting screw counterclockwise by approximately 1/4 of a turn. Recheck the new setting, and readjust the setting, if necessary.

   Please, review the remaining examples:

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   Table 16

   Example #2
   Actual Reading	(2.77 mm)
   Desired Reading	(1.85 mm)
   Difference	(0.92 mm)

   Since the desired setting is lower than the actual reading, turn the adjusting screw clockwise by approximately 1 1/8 of a turn. Recheck the new setting, and readjust the setting, if necessary.

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   Table 17

   Example #3
   Actual Reading	(-1.05 mm)
   Desired Reading	(-1.25 mm)
   Difference	(0.20 mm)

   Negative numbers work differently than positive numbers. If one number (-1.25) has a larger value than the other number (-1.05), the first number is actually less than the other number. Therefore, the desired setting is lower than the actual reading. Turn the adjusting screw clockwise by approximately 1/4 of a turn. Recheck the new setting, and readjust the setting, if necessary.

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   Table 18

   Example #4
   Actual Reading	(-2.77 mm)
   Desired Reading	(-1.85 mm)
   Difference	(0.92 mm)

   Since the desired setting is higher than the actual reading, turn the adjusting screw counterclockwise by approximately 1 1/8 of a turn. Recheck the new setting, and readjust the setting, if necessary.

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   Table 19

   Example #5
   Actual Reading	(+1.05mm)
   Desired Reading	(-1.25 mm)
   Difference	(2.30 mm)

   The desired setting is lower than the actual reading. Therefore, turn the adjusting screw clockwise by approximately 2 7/8 of a turn. Recheck the new setting, and readjust the setting, if necessary.

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   Table 20

   Example #6
   Actual Reading	(-1.05mm)
   Desired Reading	(+1.25 mm)
   Difference	(2.30 mm)

   The desired setting is higher than the actual reading. Turn the adjusting screw counterclockwise by approximately 2 7/8 of a turn. Recheck the new setting, and readjust the setting, if necessary.

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Illustration 63	g00320508
Adjusting the Fuel Setting (20) 6V-2105 Rack Adjusting Tool .

7. Use 6V-2105 Rack Adjusting Tool (20) to loosen the locknut for the adjusting screw. Also, use this tool in order to turn the locknut.

8. Adjust the fuel setting screw by the number of turns that were determined in Step 6. Always recheck the fuel setting after you adjust the setting. Adjust the setting again, if necessary.

Fuel System With a Torque Spring

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Illustration 64	g00320505
Checking the Static Fuel Setting (16) 8T-0500 Continuity Tester. (17) Rack contact screw. (18) Adjustment screw cover.

1. Fasten the clip end of 8T-0500 Continuity Tester (16) to rack contact screw (17). Connect the other end to an electrical ground.

2. Hold the governor control lever in the FUEL-ON position. Fully rotate the governor control lever in a counterclockwise direction.

3. Turn rod (13) on 6V-7941 Compressor Assembly (15) clockwise until the light in the continuity tester (16) goes out.

   After the light goes out, the hands on the dial indicator will move for an additional 2 mm in the negative direction.

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NOTICE
Do not turn the rod any further inward if the rod begins to tighten. Damage to the governor can occur if the rod is turned further inward.

4. Slowly turn rod (13) counterclockwise until the circuit tester light just turns on. This is the static fuel setting.

   Note: See the TMI for more information on the correct static fuel setting.

   Note: There will be a small, initial amount of movement by the indicator hands. Then, the indicator hands will stop moving while the rod is turned out for another 1 1/2 turns. Now, the indicator hands will begin to move again. The indicator hands will follow the turning of the rod until the setting is reached. Remember to turn the rod slowly so the rack can follow the governor components.

5. Slowly turn rod (13) outward until the indicator hands stop moving. Then, turn the rod outward for an additional 1 to 2 turns.

6. Push in on the rack stop collar. The new reading on the dial indicator is the Full Torque Setting. Refer to the TMI for more information.

   Note: On later engines, the dimension for the Full Torque Setting is given on the Engine Information Plate. The Full Torque Setting is a direct reading on the dial indicator.

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   Table 21

   Example #1
   Static Fuel Setting	(2.18 mm)
   Static Full Torque Setting	(3.18 mm)
   Torque Rise Differential	(1.00 mm)

7. If the fuel setting or the full torque setting is not correct, remove adjustment screw cover (18) from the rear of the governor housing.

8. Refer to Table 21. Determine the changes of the settings. Refer to Table 14 in order to determine the number of turns for the adjustment screws.

9. Use the 6V-2105 Rack Adjusting Tool to loosen the locknut for the adjusting screw. Also use this tool in order to turn the locknut.

10. If both settings need to be increased turn the torque adjustment screw counterclockwise for the same number of turns as the fuel setting adjustment screw. If the static fuel setting is going to be decreased, it is not necessary to change the torque rise setting at this time.

11. Adjust the fuel setting screw by the number of turns that were determined in Step 8. Always recheck the fuel setting after you adjust the setting. Adjust the setting again, if necessary.

12. After the static fuel setting is correct, adjust the torque rise adjustment screw by the number of turns that were determined in Step 8. Always recheck the fuel setting after you adjust the setting. Adjust the setting again, if necessary.

Engine Speed Measurement

Table 22

Required Tools
Part Number	Part Name	Quantity
9U-7400 6V-4950	Multitach or Speed Pickup	1

Illustration 65	g00320509
9U-7400 Multitach (1) Carrying case. (2) Power cable. (3) Tachometer generator. (4) Tachometer drive group. (5) Multitach.

The 9U-7400 Multitach can measure engine speed from a tachometer drive on the engine. This multitach can also measure engine speed from the tracking of tape on a rotating engine part.

Note: See Special Instruction, NEHS0605. This information is provided with the 9U-7400 Multitach. This information also provides instructions for the test procedure.

The 6V-4950 Speed Pickup can be used as a diagnostic tool accessory with a 9U-7400 Multitach.

Illustration 66	g00320510
6V-4950 Speed Pickup (6) 1U-9139 Fuel Line Pickup. (7) 6V-6113 Pickup Amplifier .

The 6V-4950 Speed Pickup can be used on all Caterpillar Diesel Engines that are equipped with 6 mm (.25 inch) single wall fuel injection lines. This speed pickup can measure engine rpm automatically. This speed pickup can also measure engine rpm with an accuracy of ±1 rpm.

Note: See Special Instruction, SEHS8029 that is with this tooling. This publication provides instructions for using the 6V-4950 Speed Pickup .

Governor Adjustments

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NOTICE
A service technician with training in governor adjustments is the only one to make the adjustment to the set point rpm.

Check engine rpm with an accurate tachometer. See "Engine Speed Measurement".

Low Idle Adjustment

Note: You can find the correct low idle rpm in the TMI.

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Personal injury can result from rotating and moving parts. Moving fan blades and moving parts will throw or cut any object or tool that falls or is pushed into them. Ensure that no one is working on, underneath or close to the machine before starting the engine. Ensure the area is free of personnel.

Start the engine, and operate the engine until the engine reaches the normal operating temperature. Check the low idle rpm without a load on the engine. If you need to make an adjustment, use the following procedure:

1. To adjust the low idle rpm, operate the engine with the governor in the LOW IDLE position:
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   Illustration 67	g00320512
   Low Idle Adjustment (1) Cover. (2) Low idle screw.

   1. Loosen the locknut for low idle screw (2) .

   2. Find the correct low idle rpm by turning low idle screw (2) .

   3. Then, increase engine rpm, and return to low idle rpm.

   4. Recheck the low idle rpm.

   5. Tighten the locknut.

Check Set Point (Balance Point)

Table 23

Required Tools
Part Number	Part Name	Quantity
6V-4060	Engine Set Point Indicator Group	1

Illustration 68	g00320607
6V-4060 Engine Set Point Indicator Group

An engine relies on set point (balance point) for the correct operation of the engine. An engine's set point is an adjusted specification. High idle rpm is NOT an adjusted specification.

Set point (balance point) equals full load rpm plus an additional 20 rpm. Set point is a measuring point that can be measured. At set point, the fuel setting adjustment screw and the first torque spring just begin to make contact.

At this rpm, the fuel setting adjustment screw and the first torque spring still have movement between the two components. When an additional load is put on the engine, the fuel setting screw with the stop, or the first torque spring will become stable. These components stabilize after the initial contact with pressure.

Ultimately, the fuel setting adjustment screw and the first torque spring control the set point.

There is a new, more accurate method for checking the set point of the engine. Review the required tools for the new method. If these tools are not available, you can use an alternative method for checking set point.

You can use the 6V-4060 Engine Set Point Indicator Group with the 9U-7400 Multitach to check an engine's set point.

Note: See Special Instruction, NEHS0605 for instructions on the installation and usage of the engine set point indicator group.

Alternative Method for Checking Set Point

Table 24

Required Tools
Part Number	Part Name	Quantity
8T-0500	Circuit Tester	1
9U-7400	Multitach	1

If the set point is correct and the high idle rpm is within specifications, the fuel system operation of the engine is correct.

• The set point for the engine is 20 rpm greater than full load rpm.

• The set point for the engine is at the rpm when the fuel setting screw first contacts the stop, or the first torque spring.

Use the following procedure to check the set point:

Illustration 69	g00320609
Terminal Location (3) Brass terminal screw.

Note: See Special Instruction, SEHS7050, "Techniques for Loading Engines" for more information.

1. Connect an accurate tachometer to the tachometer drive.

2. Connect the clip end of the 8T-0500 Continuity Tester to brass terminal screw (3) on the governor housing.

3. Then, connect the other end of the tester to a place on the fuel system with a good ground connection.

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Personal injury can result from rotating and moving parts. Moving fan blades and moving parts will throw or cut any object or tool that falls or is pushed into them. Ensure that no one is working on, underneath or close to the machine before starting the engine. Ensure the area is free of personnel.

4. Start the engine.

5. With the engine at normal operating conditions, operate the engine at high idle.

6. Record the rpm of the engine at high idle.

7. Slowly add load to the engine until the circuit tester light just comes on.

   This is the set point.

8. Record the engine rpm at set point.

9. To ensure that the correct reading is found, repeat Step 7 several times.

10. Stop the engine.

11. Compare the records from both Steps 6 and 8 with the information on the Engine Information Plate.

    If the Engine Information Plate is not available, see the TMI.

    The tolerance for the set point is ± 10 rpm. The tolerance for high idle rpm is ± 30 rpm. If the readings from both Steps 6 and 8 are within tolerance, no adjustment is needed.

Note: In some applications, high idle rpm will be less than the lower limit. This can be caused by high parasitic loads. Loads with hydraulic pumps and loads with compressors are good examples of high parasitic loads.

Adjusting Set Point (Balance Point)

If the set point and the high idle rpm are within tolerance, no adjustment is needed.

If the set point is not correct, follow these instructions:

1. Remove cover (1), and loosen the locknut.

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Illustration 70	g00320610
Adjustment for Set Point (4) Adjustment screw.

2. Turn adjustment screw (4) in order to adjust the set point to the midpoint of the tolerance.

3. When the set point is correct, check the high idle rpm. The high idle rpm must not be more than the high limit of the tolerance.

   1. If the high idle rpm is more than the high limit of tolerance, check the governor spring and the flyweights.

   2. If the high idle rpm is less than the low limit of tolerance, check the governor for excess parasitic loads. Then, check the governor spring and the flyweights.

Dashpot Screw Adjustment

The dashpot adjustment screw does not need an adjustment normally from the factory setting. If the engine is slow in changing rpm with a change in load, the dashpot adjustment screw may possibly need an adjustment.

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Illustration 71	g00390372
Dashpot Screw Adjustment (1) Dashpot adjustment screw.

1. Turn dashpot adjustment screw (1) clockwise until the dashpot adjustment screw stops.

2. Turn dashpot adjustment screw (1) counterclockwise by 1/2 ± 1/4 turn.