Limiting Speed Governor
DETROIT DIESEL 53
position. Turn the inner adjusting screw down on the rear injector
rack control lever until a step-up in effort is noted. This will place
the rear injector rack in the full-fuel position. Turn down the outer
adjusting screw until it bottoms lightly on the injector control tube.
Then alternately tighten both the inner and outer adjusting
screws. This should result in placing the governor linkage and
control tube assembly in the same positions that they will attain
while the engine is running at full-load.
4. To be sure of proper rack adjustment, hold the speed control
lever in the full-fuel position. Press down on the injector rack
coupling causing the coupling to rotate.
This coupling is on the end of the injector
rack and fits around the ball end of the
rack control lever.
The setting is sufficiently tight if the coupling returns to its original
position. If the coupling does not return to its original position, it is
too loose. To correct, back off the outer adjusting screw slightly
and tighten the inner adjusting screw.
Fig. 2 - Positioning the Rear Injector Rack
The coupling is too tight if, when moving the speed control lever
from the idle to the maximum speed position, the injector rack
coupling becomes tight before the speed control lever reaches the end of its travel (stop under the governor cover). This
will result in a step-up in effort to move the speed control lever to its maximum speed position and a deflection in the
fuel rod (fuel rod deflection can be seen at the bend). If the coupling is found to be too tight, back off the inner adjusting
screw slightly and tighten the outer adjusting screw.
5. Manually hold the rear injector rack control lever in the full-fuel position. Turn down the inner adjusting screw on the
injector rack control lever of the adjacent injector until the injector rack has moved into the full- fuel position and the inner
adjusting screw is bottomed on the injector control tube. Turn the outer adjusting screw down until it bottoms lightly on
the injector control tube. Then alternately tighten both the inner and outer adjusting screws.
Overtightening of the injector rack control lever adjusting screws during
installation or adjustment can result in damage to the injector control tube. The
recommended torque of the adjusting screws is 24-36 in-lb,.
6. Recheck the rear injector rack to be sure that it has remained snug on the ball end of the injector rack control lever
while adjusting the adjacent injector. If the rack of the rear injector has become loose. back off the inner adjusting screw
slightly on the adjacent injector rack control lever. Tighten the outer adjusting screw. When the settings are correct, the
racks of both injectors must be snug on the ball end of their respective rack control levers.
7. Position the remaining rack control levers as outlined in Steps 5 and 6.
Adjust Maximum No-Load Engine Speed
All governors are properly adjusted before leaving the factory. However, if the governor has been reconditioned or
replaced, and to ensure the engine speed will not exceed the recommended no-load speed as given on the engine name
plate, the maximum no-load speed may be set as follows:
1. Loosen the lock nut (Fig. 3) and back off the high speed spring retainer approximately five turns.
2. With the engine at operating temperature and no- load on the engine, place the speed control lever in the full-fuel
position. Turn the high speed spring retainer IN until the engine is operating at the recommended no-load speed.
The best method of determining the engine speed is