REMOVING THE OIL PUMP ASSEMBLY

1. Oil Pump Removal Preparation

In vehicles such as the LVS, the oil pump is located inside the oil pan. For this reason it has what is known as an internal oil pump. To remove the oil pump, turn the engine upside down and remove the oil pan. Discard all gaskets and neoprene seals. Before removing the oil pump, make sure those oil pump drive gears are in good condition by performing a gear backlash test. It would just be extra work to remove the oil pump now, repair the engine, and reinstall the pump if the gears are worn excessively. Free play (backlash) between the gear teeth would grow larger and larger, and you would have to replace the oil pump in the near future. Remember, the engine is to be repaired to a like-new condition. Oil pump gear backlash is measured with a dial indicator. This instrument is attached to or placed on the engine block and the levers adjusted so that the tip of the plunger can be placed against one tooth of the driven gear. Now adjust the instrument until the dial reads zero. After the instrument is set up in this manner, turn the driven gear against the plunger tip until it is stopped by the driving gear. Then, turn the driven gear back until it contacts the next tooth and stops. The distance the dial reads, from one tooth to the next, is the backlash. Record the backlash and check it against tolerances listed in the TM for your vehicle. If the backlash is not within the tolerances, make a note of this so you will not forget to remedy it later

Oil pump backlash test

2. Oil Pump Removal Procedures

With the backlash checks complete, the oil pump is now ready to be removed. With the engine inverted on an engine stand, unbolt and remove the oil pump, the oil pickup tubes, and the oil pickup screens as one complete assembly. Discard the gasket. You can now work inside the

crankcase.

Internal dual gear oil pump (LVS)