DETROIT DIESEL
Engine Tune - Up
adjusting screw (Fig. 2). If the setting is correct, the
The letters R or L indicate the injector location in the
.0015 " movement can be seen by placing a few drops
right or left cylinder bank, viewed from the rear of the
of oil into the governor gap and pressing a screw driver
engine. Cylinders are numbered starting at the front of
against the gap adjusting screw. Movement of the cap
the engine on each cylinder bank. Adjust the No. 3L
toward the plunger will force the oil from the gap in the
injector rack control lever first to establish a guide for
form of a small bead.
adjusting the remaining injector rack control levers.
7.
Hold the gap adjusting screw and tighten the
1.
Disconnect any linkage attached to the speed
lock nut.
control lever.
8.
Recheck the gap and readjust if necessary.
2.
Turn the idle speed adjusting screw until 1/2" of
the threads (12-14 threads) project from the lock nut
9.
Stop the engine and, using a new gasket, install
when the nut is against the high-speed plunger.
the governor cover.
CAUTION: A false fuel rack setting may
Position Injector Rack Control Levers
result if the idle speed adjusting screw is not
backed out as noted above.
The position of the injector racks must be correctly set in
relation to the governor. Their position determines the
NOTE: This adjustment lowers the tension
amount of fuel injected into each cylinder and ensures
of the low-speed spring so it can be easily
equal distribution of the load.
compressed. This permits closing the low
speed gap without bending the fuel rods or
Properly positioned injector rack control levers with the
causing the yield mechanism springs to
engine at full-load will result in the following:
yield or stretch.
1.
Speed control lever at the maximum speed
3.
Back out the buffer screw approximately 5/8", if
position.
it has not already been done.
2.
Governor low-speed gap closed.
4.
Remove the clevis pin from the fuel rod and the
right cylinder bank injector control tube lever.
3.
High-speed spring plunger on the seat in the
governor control housing.
5.
Loosen all of the inner and outer injector rack
control lever adjusting screws on both injector control
4.
Injector fuel control racks in the full-fuel
tubes. Be sure all of the injector rack control levers are
position.
free on the injector control tubes.
6.
Move the speed control lever to the maximum
speed position; hold it in that position with light finger
pressure. Turn the inner adjusting screw on the
Fig. 3 - Positioning No. 3L Injector Rack
Fig 4 - Checking Rotating Movement of
Control Lever
Injector Control Rack
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