Fuel System Operation and Tests
CHECK AND ADJUST ENGINE SPEEDS ON
NOTE: Before checking and adjusting engine speed,
make sure engine has reached its normal
CHECK SLOW AND FAST IDLE SPEEDS:
1. Start engine and run at 50% load and rated speed until
engine reaches normal operating temperature.
2. Stop engine and disconnect speed control rod from
A--Slow Idle Adjusting Screw
fuel injection pump throttle lever (C).
B--Fast Idle Adjusting Screw
NOTE: Refer to FUEL INJECTION PUMP
SPECIFICATIONS, earlier in this group, for slow
and fast idle speeds.
3. Start engine and move injection pump lever to slow
idle position against slow idle adjusting screw (A).
Compare reading with specifications. Adjust slow idle
as necessary as detailed below.
4. Move injection pump lever to fast idle position against
fast idle adjusting screw (B). Using a tachometer, read
and record engine speed. Compare reading with
IMPORTANT: If fast idle is not within specification,
have an authorized diesel repair station,
servicing dealer, or engine distributor
adjust as necessary.
ADJUST SLOW IDLE SPEED:
Move pump throttle lever to slow idle position against slow
idle adjusting screw (A). See specifications for specified
Loosen slow idle screw lock nut. Turn adjusting screw
clockwise to increase speed and counterclockwise to
decrease engine speed.