14.4.5 Variable Speed Governor
DETROIT DESIEL 53
becomes tight before the governor stop lever reaches
the end of its travel. This will result in a stepup in effort
required to move the stop lever to the RUN position and
a deflection in the fuel rod (fuel rod deflection can be
seen at the bend). If the rack is found to be too tight,
back off the inner adjusting screw slightly and tighten
the outer adjusting screw.
8. Remove the clevis pin from the fuel rod and the left
bank injector control tube lever.
9. Insert the clevis pin in the fuel rod and the right
cylinder bank injector control tube lever and position the
No. 3R injector rack control lever as previously outlined
in Step 6 for the No. 3L control lever.
10. Insert the clevis pin in the fuel rod and the left bank
Fig. 3. - Positioning No. 3L Injector Rack
injector control tube lever. Repeat the check on the 3L
Control Lever
and 3R injector rack control levers as outlined in Step 7.
5. Move the speed control lever to the maximum
Check for and eliminate any deflection which may occur
speed position.
at the bend in the fuel rod where it enters the cylinder
head.
6. Move the stop lever to the RUN position and hold it
in that position with light finger pressure. Turn the inner
11. Manually hold the No. 3L injector rack in the full
adjusting screw of the No. 3L injector rack control lever
fuel position, with the lever on the injector control tube,
down (Fig. 3) until a slight movement of the control
and turn the inner adjusting screw of the No. 2L injector
tube is observed, or a step-up in effort to turn the screw
rack control lever down until the injector rack of No. 2L
driver is noted. This will place the No. 3L injector rack
injector has moved into the full-fuel position. Turn the
in the full-fuel position. Turn the outer adjusting screw
outer adjusting screw down until it bottoms lightly on the
down until it bottoms lightly on the injector control tube.
injector control tube. Then alternately tighten both the
Then alternately tighten both the inner and outer
inner and outer adjusting screws.
adjusting screws.
12. Recheck the No. 3L injector rack to be sure that it
NOTE: Overtightening of the injector
has remained snug on the ball end of the rack control
rack control lever adjusting screws
lever while positioning the No. 2L injector rack. If the
during installation or adjustment can
rack of the No. 3L injector has become loose, back off
the inner adjusting screw slightly on No. 2L injector rack
result in damage to the injector
control lever and tighten the outer adjusting screw.
control tube.
The recommended
When the settings are correct, the racks of both injectors
torque of the adjusting screws is 24-
must be snug on the ball end of their respective control
36 in-lb.
levers.
The above steps should result in placing the governor
13. Position the IL injector rack control lever as outlined
linkage and control tube in the respective positions that
in Steps 11 and 12.
they will attain while the engine is running at full load.
14. Position the No. 2R and IR injector rack control
7. To be sure the control lever is properly adjusted,
levers as outlined above for the left cylinder bank in
hold the stop lever in the RUN position and press down
Steps II through 13.
on the injector rack with a screw driver or finger tip
causing the rack to rotate. The setting is sufficiently
15. Install the valve rocker covers.
tight if the rack returns to its original position. If the rack
does not return to its original position, it is too loose. To
Adjust Maximum No-Load Speed
correct this condition, back off the outer adjusting screw
The maximum no-load speed varies with the full-load
slightly and tighten the inner adjusting screw. The
operating speed desired.
setting is too tight if, when moving the stop lever from
the STOP to the RUN position. the injector rack
1971 General Motors Corp.
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