G3612 and G3616 Engines Caterpillar

Many procedures (disassembly and assembly, testing and adjusting, etc.) require the timing of the engine or the engine components. The engines are considered in time when the following conditions are met:

• The No. 1 cylinder is at the top center (TC) position on the compression stroke.

• The crankshaft timing pin is engaged in the bracket which is attached to the crankshaft.

• Both camshaft timing pins are engaged in the holes in the camshaft assemblies.

Engine Rotation

When you view the engine from the flywheel end, the SAE standard engine crankshaft rotation is counterclockwise.

Note: The front end of the engine is opposite the flywheel end of the engine.

The left side and the right side are viewed from the flywheel end of the engine.

Engine Prelubrication

Many service and inspection procedures require rotation of the engine crankshaft. The prelubrication of the engine is required when the crankshaft is rotated during normal maintenance operations. This includes adjusting the valves and starting the engine.

The push button for the engine prelube is located on the panel for the Engine Supervisory System. The push button provides a manual method in order to prelube the engine.

Do not use the air or electric starting motors to rotate the crankshaft. If the crankshaft is rotated too fast, oil from the prelube pump will not be enough to protect the engine.

Use the manual barring group to rotate the engine for service work. Leave the prelube pump on during crankshaft rotation. Damage can result if the crankshaft is rotated on dry bearing surfaces.

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NOTICE
In order to avoid possible damage to the engine, the prelube pump should not be operated continuously for extended periods of time. During repairs, if the prelube pump has run for more than three hours continuously, any oil that may have collected in the cylinders and/or above the valves should be removed before attempting to start the engine.

Finding the Top Center Compression Position for No. 1 Cylinder

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Illustration 1	g00311103
Location of the timing pin (1) Manual barring group (2) Storage position of the timing pin

1. Remove the crankshaft timing pin from storage position (2) of the timing pin. The storage position of the timing pin is located below the manual barring group (1). The manual barring group is located on the right side of the rear housing.

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Illustration 2	g00311105
Installation of the crankshaft timing pin (3) Flywheel timing bracket (4) Mounting bracket for the timing pin (5) Timing pin

2. Prelube the engine. Use the manual barring group to turn the engine flywheel in the direction of normal engine rotation. Turn the engine until crankshaft timing pin (5) can be installed through the mounting bracket for the timing pin (4). Ensure that the crankshaft timing pin is engaged in flywheel timing bracket (3) .

   Note: If the flywheel is turned beyond the point of installation in the flywheel timing bracket, the backlash must be removed from the timing gears. Turn the flywheel in the opposite direction of normal rotation for approximately 20 degrees. Then turn the flywheel in the direction of normal engine rotation until the timing pin can be installed in the bracket assembly. This procedure ensures that the backlash is removed from the timing gears.

   Note: There is an alternate method that can be used to determine that the No. 1 cylinder is at TC. Visually check the location of the hole in the flywheel. If the No. 1 cylinder is at TC, the hole in the flywheel for the crank angle sensor (CAS) is positioned directly opposite the CAS.

3. Remove the valve cover from the No. 1 cylinder head.

4. The inlet and exhaust valves for the No. 1 cylinder are fully closed if No. 1 piston is on the compression stroke and the rocker arms can be moved by hand. If the rocker arms cannot be moved and the valves are slightly open, the No. 1 piston is on the exhaust stroke. Refer to "Crankshaft Positions for Valve Lash Setting" in order to determine the correct cylinders that need to be checked and/or adjusted for the stroke position of the crankshaft when the timing pin has been installed in the crankshaft.

   Note: When the actual stroke position is identified, and the other stroke position is needed, remove all timing pins from the engine. Turn the flywheel for 360 degrees in the direction of the normal rotation.

Illustration 3	g00471973
G3612 Engine cylinder and valve location (A) Inlet valve (B) Gas admission valve (C) Exhaust valve

Illustration 4	g00472128
G3616 Engine cylinder and valve location (A) Inlet valve (B) Gas admission valve (C) Exhaust valve

Camshaft Timing Check

1. Remove rear camshaft inspection covers from both sides of the engine.

2. Put the No. 1 piston at the TC position on the compression stroke. Refer to "Finding the Top Center Compression Position for No. 1 Cylinder".

3. When the crankshaft timing pin is installed and the No. 1 piston is on the compression stroke, remove the camshaft timing pin from the storage position.

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Illustration 5	g00311143
Installation of camshaft timing pin (1) Timing pin (2) Camshaft

4. Install timing pin (1) through the timing pin hole and into the hole in camshaft (2) .

5. If the timing pin does not go into the hole in the camshaft, the engine is not timed and the camshaft position must be adjusted. Refer to "Camshaft Timing Adjustment".

Camshaft Timing Adjustment

Note: Before you perform any timing adjustments,check the timing in order to ensure that an adjustment is necessary. Refer to "Camshaft Timing Check ".

If the camshaft is not timed with the crankshaft, the camshaft drive gear must be removed and the camshaft must be rotated. Follow steps 1 through 7 if adjustment of the camshaft is necessary.

1. Put the No. 1 cylinder in the TC position of the compression stroke and install the crankshaft timing pin. Remove all of the valve covers from the side of the engine that requires adjustment.

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Illustration 6	g00311255
(1) Bolts (2) Rocker arm shaft

2. Loosen bolts (1) that hold rocker arm shafts (2) until all of the rocker arms are free from the valve bridges.

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Illustration 7	g00488801
Rear view of the engine (3) Camshaft drive gear covers

3. Remove the crankshaft timing pin and camshaft drive gear covers (3) from the rear housing.

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Illustration 8	g00311258
(4) Camshaft drive gear (5) Bolts (6) Bolt (7) Washer (8) Plate

4. Loosen camshaft drive gears (4) by using the following procedure:

   1. Use a 6V-6080 Torque Multiplier Gp and a 5P-1748 Socket to loosen bolt (6) .

   2. Remove bolt (6) and washer (7). Remove bolts (5) and plate (8) .

   3. Put washer (7) between the camshaft and plate (8). Refer to Illustration 8. Install bolt (6) finger tight.

   4. Install bolts (5) finger tight.

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   Sudden movement of camshaft drive gear can occur when the camshaft drive gear is pulled off the taper of the camshaft. To prevent possibly personal injury, be sure that the bolt is installed (finger tight) to restrict the movement of the camshaft drive gear when the camshaft drive gear is pulled off of the taper of the camshaft.

   5. Tighten bolts (5) evenly in order to pull camshaft drive gear (4) off the taper of the camshaft.

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Illustration 9	g00311259
(9) Camshaft timing pin

5. Install the crankshaft timing pin. Remove the camshaft timing pin from the storage location.

6. Put camshaft timing pin (9) in the timing pin hole. Rotate the camshaft until the timing pin goes into the hole in the camshaft.

7. After the camshaft is timed with the crankshaft, tighten camshaft drive gear (4) by using the following procedure:

   1. Remove bolts (5) and (6), plate (8) and washer (7) .

   2. Install washer (7) and bolt (6). Tighten bolt (6) by hand.

   3. Remove the crankshaft timing pin and the camshaft timing pin.

   4. Turn the flywheel in the opposite direction of normal rotation for a minimum of 20 degrees.

   5. Turn the flywheel in the direction of normal engine rotation until the crankshaft timing pin can be reinstalled in the crankshaft. This procedure holds the backlash in the timing gears in the direction of normal engine rotation.

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   NOTICE
   If the crankshaft timing pin location is missed, do not turn the flywheel in the opposite direction in order to install the crankshaft timing pin.

   Note: If the crankshaft timing pin location is missed, repeat Steps 7.d and 7.e.

   6. Reinstall the camshaft timing pin in order to verify the camshaft position. To prevent damage to the timing pins, remove the crankshaft timing pin and the camshaft timing pin before tightening bolt (6) .

   7. Use a 6V-6080 Torque Multiplier Gp and a 5P-1748 Socket to tighten bolt (6) to a torque of 2000 ± 275 N·m (1480 ± 200 lb ft).

   8. Use a hammer to strike plate (8). Repeat Step 7.g.

   9. Repeat Step 7.h until there is no movement of the gear on the shaft at full torque.

8. Repeat the "Camshaft Timing Check" procedure to verify the correct crankshaft to camshaft timing. If the camshaft timing is not correct, repeat the "Camshaft Timing Adjustment" procedure.

9. Remove the crankshaft timing pin and camshaft timing pin. Return the pins to the storage locations. Install the camshaft inspection covers on the side of the cylinder block.

10. Install camshaft drive gear covers (3) on the rear housing.

11. Tighten the bolts that hold the rocker arm shafts in position, and adjust the valve lash.

12. Install the valve covers.

Bridge Adjustment

If the cylinder head is disassembled, keep the bridges with the respective valves. To adjust the bridges, use the procedure that follows:

Note: The bridges can be adjusted without removal of the rocker arms and shafts. Valves must be fully closed when adjustment is made. Refer to "Finding the Top Center Compression Position for No. 1 Cylinder" and "Crankshaft Positions for Valve Lash Setting" in order to determine when the valves are fully closed.

Illustration 10	g00311260
(1) Rocker arm (2) Valve cover (3) Valve bridge (4) Adjusting screw and locknut for the valve bridge (5) Bridge dowel

Note: If the cylinder head is not disassembled omit Steps 1 and 2.

1. If the cylinder head has been disassembled, check that the bridge dowels are installed to the correct height. Lubricate the bridge dowel, the bridge dowel bore and the top contact surface of the bridge.

2. Install the bridge on the dowel.

3. Remove valve cover (2) and loosen the locknut on adjusting screw (4). Loosen the adjustment screw for several turns.

4. Press firmly on rocker arm (1) at the area of contact with bridge (3). Turn the adjusting screw in the clockwise direction until the screw just contacts the valve stem.

5. Turn the adjusting screw for an additional 45 ± 5 degrees. This will equalize clearance between the bridge and bridge dowel (5) .

6. Hold the adjusting screw in order to maintain 45 ± 5 degrees. Tighten the locknut to a torque of 100 ± 15 N·m (75 ± 11 lb ft).

7. Ensure that the valve lash is correct. Refer to "Valve Lash", for the procedures to use.

Crankshaft Positions for Valve Lash Setting

Illustration 11	g00471973
G3612Engine cylinder and valve location (A) Inlet valve (B) Gas admission valve (C) Exhaust valve

Table 1

Crankshaft Positions for Valve Lash Setting
G3612 Engine	TC Compression Stroke	TC Exhaust Stroke
Standard Counterclockwise Rotation (1)
Inlet Valves	1-3-6-7-10-12	2-4-5-8-9-11
Exhaust Valves	1-4-5-6-9-12	2-3-7-8-10-11
Gas Admission Valves	1-6-7-9-10-12	2-3-4-5-8-11
Firing Order	1-12-9-4-5-8-11-2-3-10-7-6

( 1 )

Put the No. 1 piston at the top center (TC) position. Ensure the identification for the correct stroke. Refer to "Finding the Top Center Compression Position for No. 1 Cylinder". After the adjustments are made for the correct cylinders, remove the timing pin. Turn the flywheel for 360 degrees in the direction of normal engine rotation. This will put No. 1 piston at the TC position on the opposite stroke. Install the timing pin in the crankshaft and complete the adjustments for the cylinders that remain.

Illustration 12	g00472128
G3616 Engine cylinder and valve location (A) Inlet valve (B) Gas admission valve (C) Exhaust valve

Table 2

Crankshaft Positions for Valve Lash Setting
G3616 Engine	TC Compression Stroke	TC Exhaust Stroke
Standard Counterclockwise Rotation (1)
Inlet Valves	1-2-5-7- 8-12-13-14	3-4-6-9- 10-11-15-16
Exhaust Valves	1-2-3-4- 5-6-7-8	9-10-11-12- 13-14-15-16
Gas Admission Valves	1-2-5-6- 7-8-13-14	3-4-9-10- 11-12-15-16
Firing Order	1-2-5-6-3-4-9-10- 15-16-11-12-13-14-7-8

( 1 )

Put the No. 1 piston at the TC position. Ensure the identification for the correct stroke. Refer to "Finding the Top Center Compression Position for No. 1 Cylinder". After the adjustments are made for the correct cylinders remove the timing pin. Turn the flywheel for 360 degrees in the direction of normal engine rotation. This will put No. 1 piston at the TC position on the opposite stroke. Install the timing pin in the crankshaft and complete the adjustments for the cylinders that remain.

Valve Lash

Table 3

Tools Needed		Quantity
4C-6593	Adjustment Tool	1
6V-3075	Dial Indicator	1
8S-3675	Indicator Contact Point	1

Valve lash is measured between the rocker arm and the valve bridge. All measurements and adjustments must be made with the engine stopped, and the valves fully closed.

Valve Lash Check

Measure the inlet valve lash and the exhaust valve lash. Perform checks and adjustments with the engine stopped. The valves must be fully closed. If the measurements are within the tolerance that is given in Table 4, an adjustment is not necessary. There is no range for the gas admission valve.

Table 4

Valve Lash Check with the Engine Stopped
Valves	Acceptable Range for Lash
Inlet	0.42 to 0.58 mm (0.017 to 0.023 inch)
Exhaust	1.19 to 1.35 mm (0.047 to 0.053 inch)

If the measurements are not within tolerance, adjustment is necessary. Refer to "Valve Lash Adjustment".

Valve Lash Adjustment

Table 5

Tools Needed		Qty
4C-6593 Adjustment Tool  (1)		1
6V-3075 Dial Indicator  (1)		1
8S-3675 Indicator Contact Point  (1)		1
214-1168 Socket  (2)		1
5P-0333 Wrench  (2)		1

( 1 )	Insert the contact point into the dial indicator. Insert the dial indicator into the adjustment tool. Tighten the retaining screw finger tight.
( 2 )	To facilitate the use of a torque wrench, weld the jaw of the 5P-0333 Wrench around the top end of the 1U-7133 Socket .

Valve lash dimensions are made to specific values. No tolerance is provided.

Use the procedure that follows for adjustment of the valves:

1. Put the No. 1 piston at the TC position. Refer to "Finding the Top Center Compression Position for No. 1 Cylinder".

Note: Before any actual adjustments are made, lightly tap each rocker arm at top of adjustment screw with a soft hammer in order to ensure that the lifter roller is seated against the base circle of the camshaft lobe.

2. Insert the 8S-3675 Indicator Contact Point into the 6V-3075 Dial Indicator. Insert the 6V-3075 Dial Indicator into the 4C-6593 Adjustment Tool. Tighten the retaining screw finger tight.

3. Install the adjustment tool on the rocker base. Thread the adjustment tool into the hole that is nearest to the end of the rocker arm. Position the contact point of the dial indicator over the flat area on the end of the rocker arm. Tighten the knob. Rotate the dial indicator so the dial indicator can be easily read. Check that the tool is rigid. Check that the tip of the dial indicator moves freely.

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Illustration 13	g00311261
An installed 4C-6593 Adjustment Tool

4. Loosen the adjustment screw locknut for the rocker arm. Turn the rocker arm adjustment screw clockwise until there is no valve lash. Turn the valve adjusting screw counterclockwise. The correct valve lash is zero. At this point, the valves are fully closed.

5. Zero the dial indicator.

6. Lift up firmly on the valve end of the rocker arm. Turn the valve adjusting screw until you achieve the correct lash setting.
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   Table 6

   Valve Lash Setting with Engine Stopped
   Inlet	0.50 mm (0.020 inch)
   Exhaust	1.27 mm (0.050 inch)

7. Try to move the rocker arm by a small amount while you are lifting the rocker arm. The dial indicator reading will vary. Read the dial indicator when the rocker arm fits in the groove for the rocker arm.

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Illustration 14	g00311262

8. After each adjustment, tighten the nut for the adjustment screw to a torque of 200 ± 25 N·m (150 ± 18 lb ft). Check the adjustment again. Repeat the procedure, if necessary.

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Illustration 15	g00311283

9. Tighten the adjustment screw locknut.

10. Repeat Step 3 through Step 9 for each valve.

11. After all valves are adjusted for the TC compression stroke, remove the crankshaft timing pin. Rotate the flywheel for 360 degrees in the direction of normal crankshaft rotation. This will place the No. 1 piston at TC exhaust stroke. Install the timing pin. Complete the adjustments for the cylinders that remain.

Valve Lash Adjustment for the Gas Admission Valve

1YG1-68 and ; 4CG1-48

1. Put the No. 1 piston at the TC position. Refer to "Finding the Top Center Compression Position for No. 1 Cylinder".

2. For each cylinder that is in the correct crankshaft position, turn the adjustment screw for the gas admission valve clockwise until the cross shaft cannot be turned by hand.

3. Turn the adjustment screw for the gas admission valve counterclockwise while you are counting the clicks. Continue to turn the adjustment screw for a total of nine clicks.

Note: The adjusting screw for the gas admission valve does not require a locknut.

1YG69-81 and ; 4CG49-56

1. Put the No. 1 piston at the TC position. Refer to "Finding the Top Center Compression Position for No. 1 Cylinder".

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Illustration 16	g00311285
Assembled tooling (1) 7H-1645 Holding Rod (2) 7H-1948 Swivel Clamp (3) 7H-1945 Holding Rod (4) 7H-1942 Dial Indicator (5) 4C-6593 Adjustment Tool

2. Put swivel clamp (2) on holding rod (1). Insert the holding rod into adjustment tool (5). Insert holding rod (3) in the swivel clamp. Install dial indicator (4) on the end of holding rod (3) .

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Illustration 17	g00311287
Gas admission valve (6) Adjusting screw (7) Rocker arm (8) Pin (9) Pushrod (10) Adjusting screw locknut

3. Install the valve adjusting tool and the assembled tooling on the rocker base. Position the end of the dial indicator on pin (8). The pin is located on the side of rocker arm (7) for the gas admission valve. Adjust the tooling so that the stem of the dial indicator and pushrod (9) for the gas admission valve are in a straight line. Position the dial indicator in order to easily read the indicator dial. Tighten all adjusting knobs.

4. Loosen adjusting screw locknut (10) of the rocker arm that is for the gas admission valve. Turn rocker arm adjustment screw (6) clockwise until there is no valve lash. Turn the valve adjusting screw counterclockwise. The correct valve lash is zero. At this point, the valves are fully closed.

5. Zero the dial indicator.

6. Lift up on the valve end of rocker arm (7). Turn valve adjusting screw (6) until the dial indicator reads the correct valve lash setting.
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   Table 7

   Valve Lash Setting with Engine Stopped
   Gas Admission Valve	0.64 mm (0.025 inch)

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Illustration 18	g00311288
Valve lash adjustment

7. After each adjustment, tighten the nut for the adjustment screw to a torque of 30 ± 4 N·m (22 ± 3 lb ft). Recheck the valve lash setting. Repeat the adjustment procedure, if necessary.

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Illustration 19	g00311289

8. Tighten the adjustment screw locknut.

9. Move to the next valve and repeat the procedure.

10. After all valves are adjusted for the TC compression stroke, remove the crankshaft timing pin. Rotate the flywheel for 360 degrees in the direction of the normal crankshaft rotation. This will put No. 1 piston at TC exhaust stroke. Install the timing pin. Complete the adjustments for the cylinders that remain.

1YG82-UP and ; 4CG57-UP

Table 8

Valve Lash Setting with Engine Stopped
Gas Admission Valve	0.64 mm (0.025 inch)

1. Put the No. 1 piston at the TC position. Refer to "Finding the Top Center Compression Position for No. 1 Cylinder".

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Illustration 20	g00498237
Rocker arm with pin (1) 146-2742 Gas Inlet Valve Test Tool (2) Pin

2. Install the dial indicator onto test tool (1). Install the test tool onto the rocker base. If the rocker assembly has pin (2) in the side, align the tip of the dial indicator with the center of the pin.

   Note: Make sure that the rocker arm is pressed to the left in order to indicate the maximum lash.

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Illustration 21	g00500314
Rocker arm with a counterbore (3) Counterbore

3. If the rocker arm has counterbore (3), align the tip of the dial indicator with the center of the counterbore.

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Illustration 22	g00500316

4. Lift on the end of the rocker arm that has the adjusting screw. Zero the dial indicator.

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Illustration 23	g00500317

5. While you are firmly rotating the rocker arm in the opposite direction, push the rocker arm toward the exhaust valve rocker arm.

6. Read the gas admission valve lash on the dial indicator. If the valve lash is within specifications, remove the tooling and go to the next valve.
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   Table 9

   Valve Lash Setting with Engine Stopped
   Gas Admission Valve	0.64 mm (0.025 inch)

7. After each adjustment, tighten the nut for the adjustment screw to a torque of 30 ± 4 N·m (22 ± 3 lb ft). Recheck the valve lash adjustment. Repeat the procedure, if necessary.

8. If the lash is not within specifications, loosen the adjusting locknut. While you are holding the rocker arm in the position from Step 5, turn the adjusting screw until the correct lash is seen on the dial indicator.

9. Perform the procedure for the remaining valves.

10. After all valves are adjusted for the TC compression stroke, remove the crankshaft timing pin. Rotate the flywheel for 360 degrees in the direction of the normal crankshaft rotation. This will put No. 1 piston at the TC exhaust stroke. Install the timing pin. Complete the adjustments for the cylinders that remain.

Crank Angle Sensor and Speed Sensors

Use the following procedure in order to adjust the mounting plate for the crank angle sensor and for the speed sensors.

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Illustration 24	g00498303
124-3349 Plate

1. While the engine is stopped, assemble the timing control for the crank angle sensor in hole (E). Turn the sensor until the sensor contacts the flywheel. Unscrew the sensor by 5/8 of a turn. Tighten the locknut to a torque of 45 ± 7 N·m (33 ± 5 lb ft). The correct clearance between the sensor and the flywheel is 0.55 to 0.83 mm (0.022 to 0.033 inch).

2. Install the crankshaft timing pin. Loosen the bolts for the sensor's mounting plate. Slide the plate in order to center the crank angle sensor over the hole in the flywheel. Tighten the bolts for the sensor's mounting plate.

3. Assemble the engine speed sensor in hole (C). Turn the sensor until the magnet contacts the ring gear tooth. Unscrew the sensor by 5/8 of a turn. Tighten the locknut to a torque of 45 ± 7 N·m (33 ± 5 lb ft). The correct clearance between the sensor and the flywheel is 0.55 to 0.83 mm (0.022 to 0.033 inch).

4. When the crankshaft timing pin is installed and the crank angle sensor is centered over the hole for the flywheel, assemble the timing control's speed sensor in either hole (A), (B) or (D). Choose the hole that provides the best alignment over the center of a ring gear tooth. Turn the sensor until the magnet contacts the ring gear tooth. Unscrew the sensor by 5/8 of a turn. Tighten the locknut to a torque of 45 ± 7 N·m (33 ± 5 lb ft). The correct clearance between the sensor and the flywheel is 0.55 to 0.83 mm (0.022 to 0.033 inch).

5. Remove the crankshaft timing pin.

Magneto Installation and Timing

Illustration 25	g00488872
(1) Coupling (2) Drive slot angle

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

1. Use the manual barring group in order to put the No. 1 cylinder in the TC position of the compression stroke.

2. Check the angle of the slot that is in magneto drive coupling (1). With the engine in the TC position with the No. 1 cylinder on the compression stroke, drive slot (2) of the magneto drive coupling is at 36 ± 8 degrees. If the angle is not 36 ± 8 degrees, then loosen the coupling bolt. Rotate the coupling on the shaft until the angle is correct.

3. When the angle of coupling is correct, tighten the coupling bolt.

4. Turn the magneto's shaft until the green index mark in the timing window is at the clockwise mark.

5. Insert the magneto into the bore in the magneto drive housing. The drive tangs on the magneto should engage with the slots in the magneto drive coupling.

6. Install the bolts and the washers that hold the magneto in position.

Magneto Calibration

1. Connect the Digital Diagnostic Tool (DDT) to the DDT connector. The DDT connector is located on the panel for the Engine Supervisory System.

2. Press "Select Mode" button to display "Mag Cal Mode". Press "Select Fuel" button in order to enter "Magneto Calibration Mode".

   Note: The ECM will display "PC Cal" while the engine is in the Magneto Calibration Mode.

   Note: The DDT software will not allow the engine to be operated at more than 50 percent of the rated load while the engine is in the "Magneto Calibration Mode".

3. Start the engine. Operate the engine between 550 rpm and rated speed.

4. Loosen the magneto fastener bolts. Rotate the magneto housing until a reading of 28 ± 1 degree BTC timing is achieved.

   Note: Relocation of the magneto drive gear may be necessary in order to achieve 28 ± 1 degree BTC timing.

5. Tighten the magneto fastener bolts.

6. Enter "Engine Data" mode on the DDT. Select "Timing" on the Screen "Number 11" for DDT.

7. Operate the engine at rated speed. Compare the displayed parameters.

8. At rated speed, "Desired Engine Timing" and "Actual Engine Timing" will agree within ± 1 degree.

9. Verify that the engine performance is correct. Remove the DDT service tool.