The amount of fuel pumped per stroke is varied by
This camshaft determines vertical movement of fuel
turning the plunger in the barrel. Plunger is turned by
pump plungers and also drives the governor. The
governor action on fuel rack which engages gear
camshaft is splash lubricated by oil from governor
segment on bottom of plunger. As the cam lobe puts
housing. The fuel injection pump housing and governor
pressure on plunger, plunger inlet passage moves past
may be removed as a unit, or the governor may be
pump inlet passage, and the proper amount of fuel
enters pump. As pressure reaches 400-800 PSI the
check valve opens to allow fuel to enter the ejection line,
3-17. Fuel Injection Pump for Engine Model 687C-18-
thence to fuel injection valve in combustion chamber.
Camshaft is located in lower section of fuel pump
housing, and is driven by an off-center tang on end of
a. Removal and Installation.
accessory drive shaft.
ground wire (22) from fuel injection pump (10).
9 Housing timing
13 Governor arm
Cam timing mark
15 Governor control line
Figure 3-19. Shutoff cam, removal and installation.