D346 MARINE ENGINE Caterpillar

Power Coupling System

Usage:

Enclosed Clutches And/Or Front Power Take-Off

Checking Clutch Adjustment

While engaging the clutch to pick up the load, check the clutch adjustment. The clutch should engage with a hard push and distinct snap. If engagement is "soft", adjust the clutch.

Adjusting Clutch

1. Stop the engine and remove the clutch inspection cover.

CLUTCH INSPECTION COVER

2. Turn the clutch until the lock pin, engaged in the locking ring, is visible.

3. Pull the lock pin out and rotate the locking ring clockwise until the lock pin pops into the next notch.

PULLING LOCKING PIN

4. Test the clutch adjustment. If still too "soft", rotate the ring to the next notch. If the adjustment is too tight-turn the ring back one notch.

5. Install the cover.

Lubricating D346, D379, D398 Flywheel Clutches: And All Front Power Take-Off Clutches

Lubricate the clutch bearings with grease, 1 or 2 strokes each fitting.

1. Lubricate the shift-collar bearing; 1 fitting at top-left of center.

2. Lubricate the shaft bearing; 1 fitting on top-rear of housing.

3. Lubricate the pilot bearing; 1 fitting at the end of the shaft. If this fitting is not accessible, remove the plug located on the circumference of the shaft near the rear of the housing.

PILOT, SHIFT COLLAR AND SHAFT BEARINGS

4. Lubricate the shift lever bearings; 1 fitting on each side of the clutch housing.

LUBRICATING SHIFT LEVER BEARINGS

Lubricating D348, D349 Or D399 Engine Flywheel Clutch

1. Lubricate the shift lever bearings; 1 fitting on each side of clutch housing.

SHIFT LEVER BEARING

2. Lubricate the pilot bearing; 1 fitting at the end of shaft. If this fitting is not accessible, remove the plug located on the circumference of the shaft near the rear of the housing, and install a fitting.

PILOT AND SHIFT COLLAR BEARINGS

3. Lubricate the shift-collar bearing; 1 fitting at top-left of center.

4. Check the main shaft bearing oil reservoir level with engine stopped. Maintain the oil level at the FULL mark on the oil level gauge. Add oil through the filler tube on top of the bearing cage housing. Refer to Lubrication and Maintenance Chart for proper oil.

CHECKING OIL LEVEL

5. To drain the reservoir: Remove the drain plug located on the lower left side of the shaft bearing reservoir. Drain and install the drain plug. Fill to the FULL mark on the oil level gauge. Install the filler cap.

CLUTCH SHAFT BEARING DRAIN PLUG

Electric Set Generator

If the electric set generator is not of Caterpillar design, see the manufacturer's instructions for the required lubrication and maintenance procedures.

Inspecting Slip Ring

1. Remove the two lower panels from the rear of the generator housing.

2. Inspect the slip ring color. The slip ring color may be shiny copper to straw, or chocolate to black, but the color must be uniform to indicate satisfactory operation.

If the ring is basically one of the above shades, but contains blotches of green, blue or black, clean the ring with an electrical cleaning solvent.

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NOTICE

Do not use gasoline or carbon tetrachloride. Both solvents will dissolve insulation. The vapors from carbon tetrachloride can be harmful when inhaled.

Green blotches are caused by chlorine vapors, blue blotches are caused by sulphuric fumes, black blotches are caused by oil.

3. Inspect the slip ring for pitting. If the slip rings are rough, pitted, or worn eccentric, contact your Caterpillar dealer. The rings must be reconditioned.

4. Check the following to determine the cause for pitting:

a. Check the generator nameplate rating. The generator load must be within this rating.

b. Check brush tension (SRCR Generators only).

Inspecting Brushes

The brush must move freely within the holder, but with enough spring tension to prevent brush flotation during operation.

CHECKING BRUSH SPRING TENSION

New brush length measures 1 1/8 inch (29 mm). Replace the brushes when brush length measures 9/16 inch (15 mm).

If brush tension is weak, push the spring forward into the next notch. If the spring is in the front notch, remove the brush and check the brush length. If the brush length is less than the minimum required, install a new brush.

If the spring is moved forward and the brush tension is greater than chart specifications, release the spring one notch. Excessive spring tension will cause excessive brush wear.

Installing New Brushes

1. Release spring tension.

2. Disconnect the lead wire from the brush and pull the brush from the brush holder.

3. Insert a new brush. Be sure it moves freely in the brush holder. Connect the lead wire.

4. Place a narrow piece of "00" sandpaper between the brush and slip ring with the abrasive surface against the brush. (Never use emery cloth as the emery contains small metallic particles which will damage the copper.)

5. Engage the spring in the middle notch.

6. Slowly pull the sandpaper from beneath the brush.

7. Remove all dust with a suction hose. If suction is not available, use a very low pressure blower. Do not use metal hose tips.

8. Check brush tension.

9. Install the two panels.

Lubricating The Rear Bearing

1. Remove the two lower panels from the rear of the generator housing.

2. Remove the upper and lower grease fitting plugs.

LUBRICATION PLUGS

3. Install the grease fitting in the upper threaded hole.

4. Lubricate with grease until clean lubricant appears at the lower threaded hole.

5. Wipe off the excess grease. Install the lower plug.

6. Remove the fitting from the upper threaded hole.

7. Start the engine and allow the grease to expand from the upper hole.

8. Stop the engine. Install the plug in the upper hole and wipe off excess grease.

9. Install the two panels.

LUBRICATING BEARING

Marine Gear
For Other Than Caterpillar Marine Gears, See The Marine Gear Manufacturer's Instructions

The instructions which pertain to checking and draining marine gear oil, apply to the 7261, 7251 and 7241 Marine Gears. To service the oil filter, oil strainer, breather and output shaft seal; see the instructions concerning your specific marine gear.

Checking Oil Level

1. Check the oil level with the engine warm, idling, and the clutch engaged.

CHECKING OIL LEVEL

2. Maintain oil level at the FULL mark on the oil level gauge. Add oil through the breather tube on top of the marine gear housing. Refer to Lubrication and Maintenance Chart for proper oil to use.

ADDING OIL

Draining Lubricating Oil

1. Remove the marine gear drain plug.

REMOVING DRAIN PLUG

If a sump pump is used:

a. Connect a drain line to the top outlet of the sump pump.

SUMP PUMP VALVES

b. Be sure the valve on the engine oil pan line is closed. Marks on the valve must be turned at right angles to the direction of the oil line.

c. Open the valve on the marine gear oil line.

d. Operate the sump pump handle until the oil is drained.

2. Remove the marine gear oil filter housing drain plug.

OIL DRAIN

7261 AND 7251 MARINE GEARS

Installing Marine Gear Oil Filter Element

1. Drain the marine gear lubricating oil.

2. Remove the cover assembly - with filter attached.

REMOVING COVER AND FILTER ELEMENT

3. Remove the nut, retainer, and element from the cover.

4. Clean the filter housing and the cover assembly with clean diesel fuel or kerosene.

5. Inspect the retainer plate seal, and cover seals. Install new seals if necessary.

6. Install a new filter element, the retainer, and nut to the cover assembly. Tighten the nut to 10 ± 2 foot pounds (1,38 mkg).

ELEMENT DISASSEMBLED FROM COVER

7. Install element and cover. Tighten all bolts.

8. Install the drain plug.

Clean Marine Gear Oil Strainer

1. Remove the strainer cover.

REMOVING STRAINER COVER

2. Remove the spring washer, strainer and magnetic screen tube.

REMOVING STRAINER AND MAGNETIC SCREEN TUBE

3. Wash the strainer and magnetic screen tube in clean diesel fuel or kerosene.

If a magnet is broken, install the new magnet properly; the N poles and S poles of the magnets are adjacent to each other so that they repel instead of attract: S - N, N - S, S - N.

4. Inspect the strainer, and the seal in the cover for damage. Obtain new parts if necessary.

5. Install the magnetic core tube, strainer, spring washer, seal and cover.

Filling The Marine Gear Lube System

1. Install the marine gear drain plug, or close the sump pump valve on the oil line to the marine gear.

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NOTICE

Be sure both valves (one to the marine gear and one to the engine oil pan) are closed. Otherwise, a transfer of oil may occur during operation and damage could result.

2. Fill the marine gear to the FULL mark on the oil level gauge. Refer to the Lubrication and Maintenance Chart for proper oil to use.

Cleaning The Breather

1. Remove the breather.

2. Wash it in clean diesel fuel or kerosene.

3. Install the breather.

REMOVING THE BREATHER

Output Shaft Seal

Lubricate the output shaft seal, 1 fitting at top rear of marine gear. Slowly rotate the output shaft while lubricating the seal.

LUBRICATING OUTPUT SHAFT SEAL

7241 MARINE GEAR

Installing Marine Gear Oil Filter

1. Drain the marine gear lubricating oil.

2. Remove the cover assembly-with filter attached.

REMOVING COVER AND FILTER ELEMENT

3. Remove the nut, retainer, and element from the cover.

ELEMENT DISASSEMBLED FROM COVER

4. Clean the filter housing and the cover assembly with clean diesel fuel or kerosene.

5. Inspect the retainer plate seal, and cover seals. Install new seals if necessary.

6. Install a new filter element, the retainer, and nut to the cover assembly. Tighten the nut to 10 ± 2 foot pounds (1,38 mkg).

7. Install element and cover. Tighten all bolts.

8. Install the drain plug.

Cleaning Marine Gear Oil Strainer

1. Remove the strainer cover.

REMOVING STRAINER COVER

2. Remove the spring washer, strainer and magnetic screen tube.

REMOVING STRAINER AND MAGNETIC SCREEN TUBE

3. Wash the strainer and magnetic screen tube in clean diesel fuel or kerosene.

If a magnet is broken, install the new magnet properly; the N poles and S poles of the magnets are adjacent to each other so that they repel instead of attract: S - N, N - S, S - N.

4. Inspect the strainer, and the cover seal for damage. Install new parts if necessary.

5. Install the magnetic core tube, strainer, spring washer, seal and cover.

Filling The Marine Gear Lube System

1. Install the marine gear drain plug, or close the sump pump valve on the oil line to the marine gear.

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NOTICE

Be sure both valves (one to the marine gear and one to the engine oil pan) are closed. Otherwise, a transfer of oil may occur during operation and damage could result.

2. Fill the marine gear to the FULL mark on the oil level gauge. Refer to the Lubrication and Maintenance Chart for proper oil to use.