Kohler Command PRO CS, Service Manual

Page: 30 / 162

Section 3
Troubleshooting
3.4
b. If the flywheel end of the engine is more
accessible, you can use a breaker bar and
socket on the flywheel nut/screw or a
flywheel holding tool to hold it in position.
When using these methods, you will need an
assistant to hold it during the test.
c. If the engine is mounted in a piece of
equipment, you may be able to hold it by
clamping or wedging a driven component.
Just be certain the engine cannot rotate off of
TDC in either direction.
4. Install the adapter into the spark plug hole, but
do not attach it to the tester at this time.
Leakdown Test Results
Air escaping from crankcase breather ............................................... Defective rings or worn cylinder walls.
Air escaping from exhaust system ..................................................... Defective exhaust valve.
Air escaping from carburetor .............................................................. Defective intake valve.
Gauge reading in “low” (green) zone ................................................ Piston rings and cylinder in good condition.
Gauge reading in “moderate” (yellow) zone .................................... Engine is still usable, but there is some wear
present. Customer should start planning for
overhaul or replacement.
Gauge reading in “high” (red) zone .................................................. Rings and/or cylinder have considerable wear.
Engine should be reconditioned or replaced.
5. Connect an adequate air source (70-100 psi) to the
tester.
6. Turn the regulator knob in the increase
(clockwise) direction until the gauge needle is in
the yellow “set” area at the low end of the scale.
7. Connect tester quick-disconnect to the adapter.
Note the gauge reading and listen for escaping air
at the carburetor intake, exhaust outlet, and
crankcase breather.
8. Check your test results against the table below: