Engine Speed Adjustments - Toro Groundsmaster 300 Series Service Manual

Engine Speed Adjustments (Fig. 13, 14)
Adjustments to the engine speed settings are not nor-
mally necessary unless the throttle linkage, injection
pump, or governor mechanism have been repaired,
rebuilt, replaced or are not operating correctly.
Since there is no ignition system from which to power
an electronic tachometer, a vibration-type tachometer
must be used to set engine speed.
NOTE: This engine is equipped with a special damper
spring (Fig. 14) which is designed to prevent engine
stalling when the throttle decelerated quickly. Adjust-
ment of this spring is required when adjusting the engine
rpm.
High Speed Adjustment
NOTE: Specified rpm is with no load on engine.
The high speed set bolt has been set properly and
sealed at the factory. Never tamper with the seal unless
necessary.
Idle rpm
No load governed rpm
1. The engine should be at operating temperature. Make
sure the parking brake is engaged.
2. Open and support the hood.
3. Remove sealing cap from damper spring adjusting
bolt (Fig. 14) and loosen adjusting bolt to remove
damper spring tension. NOTE: If tie rod cover was
removed, make sure governor tie rod has been pushed
to the high speed position before cover is installed.
4. Loosen the lock nut on the high speed set bolt
(Fig. 13) and adjust maximum engine speed to setting
"A" by rotating the high speed set bolt. Tighten lock nut
after adjusting.
5. Tighten damper spring adjusting bolt to adjust maxi-
mum engine speed to setting "B", then tighten locknut
to secure adjusting bolt (apply Loctite 242 or equivalent
to threads of adjusting bolt).
5. Install a wire and lead seal on high speed set bolt.
Adjustments
1500 ± 50 rpm
Setting "A" 3120 - 3160 rpm
Setting "B" 3145 - 3200 rpm
Page 4 - 14
Idle Speed Adjustment
NOTE: Specified engine rpm is with no load on engine.
1. The engine should be at operating temperature. Make
sure the parking brake is engaged.
2. Move the throttle control lever to the idle position
(against the stop plate). Open the hood.
3. Make sure throttle cable is mounted correctly to allow
complete travel of throttle control.
4. Loosen the lock nut on the low speed set bolt (Fig. 13)
and adjust idle speed to 1500 ± rpm by rotating the low
speed set bolt. Tighten the lock nut.
Figure 13
Figure 14
®
Groundsmaster 300 Series