Engine Tune-Up
DETROIT DIESEL
pin in the throttle shaft assembly entering the slot in the
differential lever.
b. Install the four cover screws and lock washers
finger tight.
c. Pull the cover assembly in a direction away
from the engine, to take up the slack, and
tighten the cover screws.
NOTE: This step is required since no dowels are
used to locate the cover on the housing.
Position Injector Rock Control Levers
The position of the injector control rack levers must be
correctly set in relation to the governor. Their position
Fig. 4 Checking Injector Control Rack
determines the amount of fuel injected into each
"' Spring"
cylinder and ensures equal distribution of the load.
3.
Move the stop lever to the RUN position and
Properly positioned injector control rack levers with the
hold it in that position with light finger pressure. Turn
engine at full-load will result in the following:
the inner adjusting screw of the rear injector rack control
lever down until a slight movement of the control tube is
1.
Speed control lever at the maximum speed
observed or a step-up in effort to turn the screw driver is
position.
noted. This will place the rear injector rack in the full-
fuel position. Turn the outer adjusting screw down until
2.
Stop lever in the RUN position.
it bottoms lightly on the injector control tube. Then
alternately tighten both the inner and outer adjusting
3.
Injector fuel control racks in the full-fuel
screws. This should result in placing the governor
position.
linkage and control tube in the respective positions that
they will attain while the engine is running at full load.
Adjust the rear injector rack control lever first to
establish a guide for adjusting the remaining levers.
NOTE: Overtightening of the injector rack
1.
Loosen all of the inner and outer injector rack
control
lever
adjusting
screws
during
control lever adjusting screws (Fig. 2). Be sure all of
installation or adjustment can result in damage
the levers are free on the injector control tube.
to the injector control tube. The recommended
torque of the adjusting screws is 24-36in- lbs.
2.
Move the speed control lever to the maximum
speed position.
4.
To be sure of proper rack adjustment, hold the
stop lever in the RUN position and press down on the
injector rack with a screw driver or finger tip and note
"rotating" movement of the injector control rack (Fig. 3).
Hold the stop lever in the RUN position and, using a
screw driver, press downward on the injector control
rack. The rack should tilt downward (Fig. 4) and, when
the pressure of the screw driver is released, the control
rack should "spring" back upward.
If the rack does not return to its original position, it is too
loose. To correct this condition, back off the outer
adjusting screw slightly and tighten the inner adjusting
screw. The setting is too tight if, when moving the stop
lever from the STOP to the RUN position, the injector
rack becomes tight before the stop lever reaches the
Fig. 3 - Checking Rotating Movement of
end of its travel. This will result in a step-up in effort
Injector Control Rack
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