Engine Tune-Up
VARIABLE SPEED MECHANICAL GOVERNOR AND INJECTOR RACK
CONTROL ADJUSTMENT
6, 8 and 12V ENGINES
tube assemblies which have a yield spring at each
The single - weight variable speed governor is mounted
injector rack control lever and only one screw and lock
on the front of the engine and is driven by the blower
nut to keep each injector rack properly positioned.
rotor.
Adjust the single screw and lock nut on each injector
rack control lever the same as for the two screw rack
After adjusting the exhaust valves and timing the fuel
control lever.
injectors, a d j u s t the variable speed mechanical
governor and injector rack control levers.
Properly positioned injector rack control levers, with
NOTE: Before proceeding with the governor and
the engine at full load, will result in the following:
i n j e c t o r rack adjustments. disconnect any
supplementary governing device. After the
1. Speed control lever at the maximum speed position.
adjustments a r e completed, reconnect and
adjust the supplementary governing device.
2. Stop lever in the Run position.
3 . High speed spring plunger is within .005" to
Adjust Governor Gap
.007" of its seat in the governor control housing.
With the engine stopped and at normal operating
4. Injector fuel control racks in the full fuel position.
temperature, adjust the governor gap as follows:
1. Disconnect any linkage attached to the governor
The letters R and L indicate the injector location in
levers.
the right or left cylinder bank, viewed from the rear of
the engine. The cylinders are numbered starting at the
2. Back out the buffer screw until
it
extends
front of the engine on each cylinder hank. Adjust the
approximately 5/8" from the lock nut.
3. Clean and remove the governor cover and valve
rocker covers. Discard the gaskets.
4. Place the speed control lever in the maximum speed
position.
5. Insert a .006" feeler gage between the spring
plunger and the plunger guide as shown in Fig. 1. If
required, loosen the lock nut and turn the adjusting
screw until a slight drag is noted on the feeler gage.
6. Hold the adjusting screw and tighten the lock nut.
Check the gap again and, if necessary, readjust.
7. Use a new gasket and install the governor cover.
Tighten the screws.
Position Injector Rock Control levers
The position
of the injector control rack levers must be
correctly set
in relation to the governor. Their position
determines
the amount of fuel injected into each
cylinder and
ensures equal distribution of the load.
Fig. 1 - Adjusting Governor Gap
Certain engines use spring-loaded injector control
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