DETROIT DIESEL 53
LIMITING SPEED MECHANICAL GOVERNOR AND
INJECTOR RACK CONTROL ADJUSTMENT
After adjusting the exhaust valves and timing the fuel
injectors, adjust the governor and position the injector
rack control levers.
NOTE: Loosen the Ioad Iimit lever for the load
limiting device, if the engine is so equipped.
Adjust Governor Gap
With the engine stopped and at operating tempera-
ture, adjust the governor gap as follows:
1. Remove the high speed spring retainer cover.
2. Back out the buffer screw until it extends 5/8"
beyond the governor housing.
3. Clean and remove the valve rocker cover.
Fig. 1 - Adjusting Governor Gap
4. Start the engine and adjust the idle speed screw
(Fig. 5) to obtain an idle speed of 500-600 rpm.
10. Install the governor cover. The governor cover
should be placed on the housing with the pin of the
NOTE: The recommended idle speed is 500-600
speed control lever projecting into the slot of the
rpm, but may vary with special engine
11. Install the screws and lock washers finger tight. Pull
the cover away from the engine and tighten the
5. Stop the engine and remove the governor cover.
screws. This step will properIy locate the cover on the
6. Start the engine and control the speed manually by
operating the injector control tube lever. The engine
speed should be between 800 and 1000 rpm.
Position Injector Rock Control levers
CAUTION: Do not overspeed the engine.
The position of the injector racks must be correctly set
in relation to the governor. Their position determines
the amount of fuel injected into each cylinder and
7. Check the gap between the low speed spring cap
ensures equal distribution of the load.
and the high speed spring plunger with a .0015"
feeler gage. If the gap setting is incorrect, reset the
Adjust the rear injector rack control lever first to
gap adjusting screw (Fig. 1). If the setting is correct.
establish a guide for adjusting the remaining injector
the .0015" movement can be seen by placing a few
rack control levers.
drops of oil into the governor gap and pressing a
1. Disconnect any Iinkage attached to the speed control
screw driver against the gap adjusting screw.
Movement of the cap toward the plunger will force the
oil from the gap in the form of a small bead.
2. Loosen all of the inner and outer injector rack
control lever adjusting screws (Fig. 2) Be sure all of
8. Hold the gap adjusting screw and tighten the lock
the levers are free on the injector control tube.
3. Move the speed control lever to the full-fuel
9. Recheck the gap and readjust if necessary.
May, 1971 SEC. 14.3.1 Page 1