DETROIT DIESEL 53
14.3-1 Limiting Speed Governor
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 he too tight, back off the
inner adjusting screw slightly and tighten the outer
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 is bottoms lightly on the injector
control tube. Then alternately tighten both the inner
and outer adjusting screws.
NOTE: Overtightening of the injector rack
control lever adjusting screws during installa-
tion or adjustment can result in damage to the
injector control tube. The recommended torque
of the adjusting screws is 24-36 in-lbs.
6. Recheck the rear injector rack to be sure that it has
Fig. 2 - Positioning the Rear Injector Rack
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
position. Turn the inner adjusting screw down on the
the inner adjusting screw slightly on the adjacent
rear injector rack control lever until a step-up in effort
injector rack control lever. Tighten the outer adjusting
is noted. This wiII pIace the rear injector rack in the
screw. When the settings are correct, the racks of both
full-fuel position. Turn down the outer adjusting screw
injectors must he snug on the ball end of their
until it bottoms lightly on the injector control tube.
respective rack control levers.
Then alternately tighten both the inner and outer
adjusting screws. This should result in placing the
7. Position the remaining rack control levers as
governor linkage and control tube assembly in the
outlined in Steps 5 and 6.
same positions that they will attain while the engine is
running at full-Ioad.
Adjust Maximum No-load Engine Speed
4. To be sure of proper rack adjustment, hold the
speed control lever in the full-fuel position. Press down
All governors are properly adjusted before leaving the
on the injector rack coupling causing the coupling to
factory. However. if the governor has been recondi-
tioned or replaced. and to ensure the engine speed will
not exceed the recommended no-load speed as given
NOTE: This coupling is on the end of the
on the engine name plate, the maximum no-load speed
injector rack and fits around the ball end of the
may be set as follows:
rack control lever.
TYPE A GOVERNOR SPRINGS (Fig. 4):
The setttng is sufficiently tight if the coupling returns
to its original position. If the coupling does not return
1. Loosen the lock nut (Fig. 3) and back off the high
to its original position, it is too loose. To correct, back
speed spring retainer approximately five turns.
off the outer adjusting screw slightly and tighten the
2. With the engine at operating temperature and no-
inner adjusting screw.
load on the engine. place the speed control lever in the
full-fuel position Turn the high speed spring retainer
The coupling is too tight if, when moving the speed
IN until the engine is operating at the recommended
control lever from the idle to the maximum speed
position, the injector rack coupling becomes tight
The best method of determining the engine speed is
before the speed control lever reaches the end of its
travel (stop under the governor cover). This will result