Engine Tune-Up
7. With the engine operating at the recommended
Adjust Maximum No-load Speed
full-load speed, apply the full rated load and recheck
the engine speed. If required, readjust the engine to
With the speed droop properly adjusted, set the
full-load speed.
maximum no-load speed as follows:
8. Remove the load and note the engine speed. If the
1. With the engine operating at no load, adjust the
zero droop setting is correct, the engine speed will
speed until the engine is operating at approximately
remain constant. If the engine speed is higher, loosen
8% higher than the rated full-load speed.
the droop adjusting knob and set the slider to a
reduced droop position.
2. Turn the maximum speed adjusting screw (Fig. 10)
i n until the screw contacts the throttle linkage
9 . When the desired minimum droop setting is
internally, limiting the maximum speed of the engine
reached, loosen the lock nut and turn the minimum
at 8% above the rated full-load speed.
droop setting screw inward until it contacts the droop
linkage within the governor. This will be felt by a
3. Hold the screw and tighten the lock nut
step-up of resistance while turning the adjusting
screw. Lock the adjusting screw in this position.
10. Loosen the droop adjusting
knob and slide the
Governors with Synchronizing Motor
droop bracket in a direction to
increase the droop.
Perform Steps 7 and 8 to check
the droop until the
Some hydraulic governors are equipped with a
desired maximum speed droop is
attained.
reversible electric synchronizing motor (Fig. 11)
mounted on the governor cover.
11. When the desired maximum droop setting is
reached, loosen the lock nut and turn the maximum
T h e adjustments on a governor equipped with a
droop setting screw inward until it contacts the droop
synchronizing motor are the same as on a governor
slider arm. Lock the adjusting screw in this position.
without the motor. However, the governor cover and
motor assembly must be removed when setting the
1 2 . Recheck the minimum and maximum droop
engine speed droop (except on a governor equipped
setting as outlined in Steps 7 and 8 and adjust the
with an external droop adjustment). The cover and
adjustment screws, if necessary, until the correct
motor must be reinstalled to check the speed droop.
settings are obtained.
VARIABLE SPEED HYDRAULIC GOVERNOR AND INJECTOR RACK CONTROL
ADJUSTMENT
16V-71 ENGINE
3 . Remove the vertical link assembly from the
The governor on the l6V engine is mounted on and
driven from the front end of the rear blower (Fig. 1).
governor operating lever and the bell crank lever.
The governor-to-injector control tube linkage is
shown in Fig. 2.
4. Loosen the bolt and slide the governor operating
lever from the serrated shaft
After adjusting the exhaust valves and timing the fuel
injectors, adjust the governor linkage and position the
injector rack control levers.
5. Place the bolt (removed from the lower end of the
vertical link) through the bell crank and into the
recessed hole in the governor drive housing (Fig. 3).
Adjust Governor Linkage and Position Injector
Rack Control levers
6. Adjust the No. 4R injector rack by turning the
1. Clean and remove the valve rocker cover from each
inner adjusting screw down until it bottoms on the
cylinder head. Discard the gaskets.
control tube (Fig. 4). Turn down the outer adjusting
screw until it also bottoms on the control tube. Then
2. Loosen all of the inner and outer injector rack
tighten both the inner and outer adjusting screws
control lever adjusting screws. Be sure all of the
alternately.
control levers are free on the control tubes.
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