Maintenance
RPM Adjustments
Maintenance
WM doc 9/18/19
3-4
3
6.
After the alternator belt has been tensioned, tighten the adjustment bolt jam nut. Tighten
the upper and lower pivots and replace the belt covers.
3.7
RPM Adjustments
WARNING!
Remove the blade before performing any engine service.
Failure to do so may result in serious injury.
Check the RPM with a tachometer every 200 hours of operation.
See Table 3-1.
Before checking the RPM, make sure belt and brake strap tensions are correct (See Saw-
mill Maintenance). Also check oil, fuel, and coolant levels.
Make sure the throttle cable does not affect the engine RPM when the clutch handle is
disengaged. Make sure the cable is not bent or kinked.
NOTE:
It is important that the
above components are aligned. Proper alignment allows any slack in the cable (when
engine is idling) to slide down into the cable spring. This maintains free operation of the
cable and prevents the cable from kinking. Make sure the shoulder bolt does not rub
against the crankcase vent tube.
1.
Start the engine to measure the low-end RPM.
2.
Refer to the engine manual to adjust the low-end RPM.
3.
Engage the clutch handle to throttle the engine and measure the high-end RPM. The
high-end RPM is factory-set at 3600. Readjust the throttle cable if necessary to increase
or reduce the high-end engine speed.
The throttle cable should be tensioned just enough so that the engine revs as soon as the
clutch/brake handle is engaged. NOTE: A properly adjusted throttle will extend the cable
spring 1/4” to 3/8” (6.4 - 9.5 mm) when running and have a slight amount of slack in the
cable when idling.
3.8
Miscellaneous Maintenance
Clean and inspect the spark arrester every 50 hours of operation. Replace if damaged.
Engine
High End RPM
Low End RPM
G38
3600
1500
TABLE 3-1
200
50
