DETROIT DIESEL
Engine Tune-Up
adjusting screw slightly and tighten the inner adjusting
No. 3L injector rack control lever down as shown in
screw slightly.
Fig. 3 until a slight movement of the control tube
lever is observed or a step-up in effort to turn the
screw driver is noted. This will place the No. 3L
The setting is too tight if, when moving the speed
injector in the full-fuel position. Turn down the outer
control lever from the no-speed to the maximum speed
adjusting screw until it bottoms lightly on the injector
position, the injector rack becomes tight before the
control tube. Then alternately tighten both the inner
speed control lever reaches the end of its travel (as
and outer adjusting screws.
determined by the stop under the governor cover).
This will result in a step-up in effort required to move
the speed control lever to the end of its travel. To
NOTE: Overtightening of the injector rack
correct this condition, back off the inner adjusting
control lever adjusting screws during installa-
screw slightly and tighten the outer adjusting screw
tion or adjustment can result in damage to the
slightly.
injector control tube. The recommended torque
of the adjusting screws is 24-36 in-lbs (3-4 Nm).
8. Remove the clevis pin from the fuel rod and the left
bank injector control tube lever.
IMPORTANT: The above step should result in
placing the governor linkage and control tube
9. Insert the clevis pin in the fuel rod and the right
assembly in the same position that they will
cylinder bank injector control tube lever and position
attain while the engine is running at full-load.
the No. 3R injector rack control lever as previously
outlined in Step 6 for the No. 3L injector rack control
7. To be sure of the proper rack adjustment, hold the
lever.
speed control lever in the maximum speed position
and press down on the injector rack with a screw
10. Insert the clevis pin in the fuel rod and the left
driver or finger tip and note "rotating" movement of
cylinder bank injector control tube lever. Repeat the
the injector control rack (Fig. 4) when the speed
check on the 3L and 3R injector rack control levers as
control lever is in the maximum speed position. Hold
outlined in Step 7. Check for and eliminate any
the speed control lever in the maximum speed position
deflection which may occur at the bend in the fuel rod
and, using a screw driver, press downward on the
where it enters the cylinder head.
injector control rack. The rack should tilt downward
(Fig. 5) and when the pressure of the screw driver is
11. To adjust the remaining injector rack control
released, the control rack should "spring" back
levers, remove the clevis pin from the fuel rods and
upward.
the injector control tube levers, hold the injector
control racks in the full-fuel position by means of the
lever on the end of the control tube, and proceed as
If the rack does not return to its original position, it is
follows:
too loose. To correct this condition, back off the outer
a. Turn down the inner adjusting screw of the
injector rack control lever until the screw bottoms
(injector control rack in the full-fuel position).
b. Turn down the outer adjusting screw of the
injector rack control lever until it bottoms on the
injector control tube.
c. While still holding the control tube lever in the
full-fuel position, adjust the inner and outer
adjusting screws to obtain the same condition as
outlined in Step 7. Tighten the screws.
CAUTION: Once the No. 3L and No. 3R
injector rack control levers are adjusted, do not
try to alter their settings. All adjustments are
made on the remaining control racks.
NOTE: Overtightening of the injector rack
Fig. 5 - Checking Injector Control Rack
control tube lever adjusting screws during
"Spring"
installation or adjustment can result in damage
to the injector control tube. The recommended
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