Generac Power Systems OHVI GSH 190, Service Manual, Page: 18 / 72

3-6
SeCTIoN 3: AIr INTAke SYSTeM ANd CArbureTIoN
FINAL ADJUSTMENT:
The following instructions apply to engines NOT equipped
with automatic idle control. If the unit has an automatic idle
control, refer to the Section 5, "Optional Idle Control."
If the engine is used to drive an AC generator set, use an
AC frequency meter to measure engine speed/frequency. Con-
nect the AC frequency meter across one of the generator’s AC
output receptacles or across the generator’s AC power winding
output leads. Read the AC output
frequency in HERTZ (cycles
per second).
If the engine is used in some other application (pressure
washer, pump, air compressor,
etc.), use a tachometer to read
the engine rpm.
. Start the engine and allow a sufficient warm-up period.
2. Hold the carburetor throttle lever against the idle speed
stop screw, then turn the idle speed
stop screw until the
correct idle speed is obtained.
a. If the driven unit is an AC generator and an AC frequency
meter is used, the correct high no-load speed is between
62-6 Hertz. (720-780 rpm).
b. If the unit is not a generator, adjust the high no-load speed
stop screw to obtain about 750 rpm.
Figure 3-7. Idle Speed Stop Screw
0C1103Arev0.indd 6 6/22/2006 10:49:56 AM