How to Rebuild the Engine Oil Pump of an International Tractor

Designed to lubricate the motor with oil, the oil pump is responsible for circulating oil throughout an internal combustion engine. International Harvester tractors are equipped with an oil pump driven by a rod resting against the crankshaft, just inside the engine casing. As the crankshaft drives the rod, gears inside the pump circulate oil throughout the engine; a sudden drop in engine oil pressure often suggests a faulty oil pump that requires rebuilding.

Instructions

1

Obtain an oil pump rebuilding kit, containing new gaskets, oil pickup tube and filter screen, at an auto or tractor supply store.

2

Drain the engine oil. Place a drain pan under the engine and remove the oil drain pan plug with a wrench. Remove the oil filter with an oil filter wrench.

3

Locate the two hoses attached to the oil pump. For ease of identification during reassembly, wrap a piece of masking tape around the oil pump hose nearest the engine. Loosen the hose clamps with a screwdriver and pull the hoses free of the pump with your hands.

4

Remove the oil pump mounting bolts from the tractor engine block with a wrench. Work the oil pump free from the engine block with your hands.

5

Disassemble the pump. Remove the bolts along the sides of the pump with a wrench. Grasp the sides of the pump with your hands and wiggle the two sections back and forth until the pump sections separate. Tap the pump gently with a rubber mallet if the sections dont separate freely.

6

Remove the gasket from the separated pump sections and the base of the pump, where the pump was attached to the engine block, with a razor blade scraper. Clean the gasket contact surfaces with a piece off 220-grit sandpaper.

7

Scratch an identifying mark on the outside of each gear with an awl. For example, mark the gear farthest to the outside edge of the pump with an O and the gear toward the center of the pump with I. Remove the retaining screws, if present, from the gear axles with a screwdriver. Pull the gears free of the pump with your fingers. Work the oil pickup tube and filter screen free from the pump, gently, with your fingers.

8

Spray all interior and exterior surfaces of the pump sections and gears with parts cleaner. Wipe the parts clean with a clean, lint-free cloth.

9

Lubricate the pump gear axle screws, the base of the new oil pickup tube and new filter screen from the rebuilding kit with motor oil. Reinstall the gears in the pump. Push the male end of the new oil pickup tube firmly into the female socket on the pump with your hands. Install the new filter screen inside the pump with your fingers.

10

Place the new pump gasket from the kit between the two pump sections. Fasten the pump sections together with the bolts and a torque wrench set to 18 foot-pounds of torque.

11

Position the new mounting gasket over the oil pump mounting bolts on the engine block. Reattach the oil pump to the engine with the mounting bolts and a torque wrench set to 22 foot-pounds of torque.

12

Replace the oil drain pan plug and tighten the plug with a wrench. Install a new oil filter on the engine, turning the filter until it is hand tight; never tighten an oil filter with a wrench.

13

Refill the crankcase with fresh motor oil of the type and grade recommend by the tractor manufacturer. Start the engine and check around the mounting surfaces of the oil pump and oil filter for leaks. Tighten the bolts and filter further if necessary.