Oil Flow For Pump and Governor.

TM5-241O-237-34

When the fuel injection pump camshaft turns, the cam moves push rod (21) and

piston (22) down. As the piston moves down, inlet check valve (23) and outlet

check valve (24) close. Pumping check valve (25) opens and allows the fuel

below the piston to move into the area above the piston. Pumping spring (26) is

compressed as the piston is pushed down by push rod (21).

As the fuel injection pump camshaft continues to turn, the cam no longer puts

force on push rod (21). Pumping spring (26) now moves piston (22) up. This

causes pumping check valve (25) to close. Inlet check valve (23) and outlet

check valve (24) will open. As the piston moves up, the fuel in the area above

the piston is pushed through the outlet check valve (24) and out pump outlet

port (27). Fuel also moves through pump inlet port (28) and inlet check valve

(23) to fill the area below piston (22). The pump is now ready to start a new

cycle.

Oil Flow For Pump and Governor. Oil from the side of the cylinder block goes to

support (29) and into the bottom of front governor housing (30). The flow of

oil now goes in three different directions.

A part of the oil goes to the rear camshaft bearing in fuel pump housing (31).

The bearing has a groove around the inside diameter. Oil goes through the

groove and into the oil passage in the bearing surface (journal) of camshaft

A drilled passage through the center of the camshaft gives oil to the

(32).

front camshaft bearing and to the thrust face of the camshaft drive gear. Drain

hole (33) in the front of fuel pump housing (31) keeps the level of the oil in

the housing even with the center of the camshaft. The oil returns to the 0il

pan through the timing gear housing.

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