Disassembly steps
Begin:
a. Remove the fuel injection pump gear. See Disassembly and Assembly, "Fuel Pump Gear - Removal".
b. Remove the valve cover. See Disassembly and Assembly, "Valve Cover - Removal and Installation".
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Note: Either of the two tools (A) can be used. Please use the tool most suitable for you.
Note: Care must be taken to ensure that the fuel pump timing is not altered during the removal of the fuel pump gear. Carefully follow these steps to remove the fuel pump gear.
Note:
Keep all parts clean and free of impurities.
Impurities will cause rapid wear and shorten the lifespan of parts.
1. Remove the plug (5) from the cylinder block. Remove the O-ring (4) from the plug (5).
2. Using tool (A), rotate the crankshaft until piston #1 is at top dead center (TDC) of its compression stroke. Refer to System Operation, Testing and Adjustment, "Finding Piston #1 at TDC".
3. Install tool (B) into the bore (Y) of the cylinder block. Use tool (B) to lock the crankshaft in place.
Note: Do not use excessive force when installing tool (B). Do not use tool (B) to hold the crankshaft in place during repairs.
4. Ensure tool (C) is installed in the bore (X) of the camshaft gear. Use tool (C) to lock the camshaft in place.
5. Ensure gears (1), (2), and (3) are marked to indicate alignment.
6. Loosen the nuts (7) on all rocker arms (8). Loosen the adjusters (6) on all rocker arms (8) until all valves are fully closed.
Note: Failure to fully loosen all adjusters may result in valves contacting the piston.
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7. Mark the plate (9) to indicate the orientation.
Note: Identifying the markings ensures the plate is installed in its original alignment position.
8. Remove the bolts (10).
9. Remove the plate (9).
10. Remove the idler gear assembly (3) and the hub (11) from the recess in the front housing.
Note: The idler gear must be tilted during disassembly.
11. Remove the hub (11) from the idler gear (3).
