M11 Series – Service Manual – 007-031   Lubricating Oil Pump

Remove the gear cover.

Refer to Procedure 001-031.

The water pump

must be removed to remove the water pump idler gear.

Drain the cooling system, and remove the water pump. Refer to the following procedures respectively:

Procedure 008-018, Procedure 008-062.

Remove the water pump idler gear.

Refer to Procedure 001-040.

CAUTION  Do not pry on the gear or pump flange. This can result in damage to the pump.

Remove the three mounting capscrews and spacers.

Use both hands to pull, or insert, two capscrews (M8 X 1.25) into the puller holes to push the pump from the engine.

Turn the main drive gear by hand to check the gears for freedom of rotation.

Inspect the gears for cracked, worn, or broken teeth.

Inspect the rear cover plate shaft bores for excessive wear or discoloration due to overheating or shaft seizure.

Measure the driveshaft and driven shaft end clearance.

If the gears are damaged, the shaft does

not turn freely by hand, or the end clearance is

not within the specifications given, the oil pump

must be replaced.

Clean the threaded lubricating pump mounting holes in the cylinder block and capscrew threads with solvent. Dry with compressed air.

Install two new o-rings on the oil pump body.

Install the thickest o-ring into the groove nearest the oil pump drive gear.

NOTE: Do

not lubricate the two oil pump body o-rings. The o-rings will swell, and the pump can

not be installed.

Use clean 15W-40 oil to lubricate the oil pump gears.

Apply a film of grease to the oil pump bore in the cylinder block.

CAUTION  The dowel pin bore in the oil pump flange (1) must be aligned with the dowel pin in the cylinder block (2) to prevent damage to the oil pump flange during installation. Do not use the mounting capscrews to pull the oil pump into the bore. This can damage the mounting flange of the oil pump.

Install the oil pump by hand.

Sealant, Part No. 3824038, or equivalent,

must be used to coat the threads of the three mounting capscrews to prevent air from being drawn past the capscrews during engine operation.

CAUTION  The shorter flange head capscrew must be used in the upper right-hand mounting hole (1) to prevent the idler gear from contacting the head of the capscrew and causing damage to the lubricating oil pump.

Install the three capscrews and spacers. Use the short flange head capscrew in the upper right hand mounting hole (1). Use the longer flange head capscrews and spacers in the other two holes.

Install the water pump idler gear.

Refer to Procedure 001-040.

Install the water pump.

Refer to Procedure 008-062.

Install the gear cover.

Refer to Procedure 001-031.

Operate the engine and check for leaks.