TM 5-3810-300-24&P-3
14 Engine Tune-Up
four-valve cylinder head, in the tune-up sequence given
below after the engine has reached normal operating
3. Adjust the governor gap.
temperature. Since the adjustments are normally made
while the engine is stopped, it may be necessary to run
4. Position the injector rack control levers.
the engine between adjustments to maintain normal
operating temperature.
5. Adjust the maximum no-load speed.
6. Adjust the idle speed.
NOTE: The exhaust valve bridges on a four-
valve cylinder head are adjusted at the time the
7. Adjust the buffer screw.
cylinder head is installed on the engine and, until
wear occurs, no further adjustment is required.
8. Adjust the throttle booster spring (variable speed
When wear is evident, perform a complete valve
governor only).
9. Adjust the fuel modulator, if used.
Use a new valve rocker cover gasket after the tune-up is
completed.
NOTE: The steps necessary to adjust an engine
with a fuel modulating governor are covered in
Tune-Up Sequence
Section 14.5.
1. Adjust the exhaust valve clearance.
2. Time the fuel injectors.
Page 378