14 Engine Tune-Up
DETROIT DIESEL 53
Adjust the governor gap.
weight variable speed governor name plate is stamped
Position the injector rack control levers.
Adjust the maximum no-load speed.
Normally, when performing a tuneup on an engine in
service, it is only necessary to check the various
Adjust the idle speed.
adjustments for a possible change in the settings.
However, if the cylinder head, governor, or injectors
Adjust the buffer screw.
have been replaced or overhauled, then certain
preliminary adjustments are required before the engine
Adjust the throttle booster spring,
The preliminary adjustments consist of the first four
NOTE: Use new valve rocker cover gasket(s)
items in the tune-up sequence. The procedures are the
after each tune-up.
same except that the valve clearance is greater for a
NOTE: If a supplementary governing device,
is used, it must be
disconnected prior to the tune-up. After the
governor and injector rack adjustments are
completed, the supplementary governing device
must be re-connected and adjusted.
To tuneup an engine completely, all of the adjustments
are made by following the applicable tuneup sequence
given below after the engine has reached the normal
Since the adjustments are
normally made while the engine is stopped, it may be
necessary to run the engine between adjustments to
maintain normal operating temperature.
Tune-Up Sequence for Mechanical Governor
Adjust the exhaust valve clearance.
Time the fuel injectors.
1972 Gel Motors Corp.