Kohler Command CV25 Service Manual

Fuel System
24 690 07 Rev. H
KohlerEngines.com
27
Troubleshooting-Carburetor Related Causes
Condition Possible Cause Conclusion
Engine starts hard, runs rough, or
stalls at idle speed.
Low idle fuel mixture/speed
improperly adjusted.
Adjust low idle speed tab, then adjust
low idle fuel needle.
Engine runs rich (indicated by black,
sooty exhaust smoke, misring, loss
of speed and power, governor
hunting, or excessive throttle
opening).
Clogged air cleaner. Clean or replace air cleaner.
Choke partially closed during
operation.
Check choke lever/linkage to ensure
choke is operating properly.
Low idle fuel mixture is improperly
adjusted.
Adjust low idle fuel needle.
Float level is set too high. Separate fuel bowl from carburetor
body. Free (if stuck), or replace oat.
Dirt under fuel inlet needle. Remove needle; clean needle and
seat and blow with compressed air.
Bowl vent or air bleeds plugged. Remove low idle fuel adjusting
needle. Clean vent, ports, and air
bleeds. Blow out all passages with
compressed air.
Leaky, cracked, or damaged oat. Submerge oat to check for leaks.
Engine runs lean (indicated by
misring, loss of speed and power,
governor hunting, or excessive
throttle opening).
Low idle fuel mixture is improperly
adjusted.
Adjust low idle fuel needle.
Float level is set too low. Separate fuel bowl from carburetor
body. Free (if stuck), or replace oat.
Idle holes plugged; dirt in fuel delivery
channels.
Remove low idle fuel adjusting
needle. Clean main fuel jet and all
passages; blow out with compressed
air.
Fuel leaks from carburetor. Float stuck. Separate fuel bowl from carburetor
body. Free (if stuck), or replace oat.
Dirt under fuel inlet needle. Remove needle; clean needle and
seat and blow with compressed air.
Bowl vents plugged. Blow out with compressed air.
Carburetor bowl gasket leaks. Replace gasket.
Fuel Shut-Off Solenoid
Most carburetors are equipped with a fuel shut-off solenoid. Solenoid is attached to fuel bowl. Solenoid has a spring-
loaded pin that retracts when 12 volts is applied to lead, allowing fuel ow to main jet. When current is removed, pin
extends blocking fuel ow.
Below is a simple test, performed with engine off, that can determine if solenoid is functioning properly:
1. Shut off fuel and remove solenoid from carburetor. When solenoid is loosened and removed, gas will leak out of
carburetor. Have a container ready to catch fuel.
2. Wipe tip of solenoid with a shop towel or blow with compressed air to remove any remaining fuel. Take solenoid to
a location with good ventilation and no fuel vapors present. You will also need a 12 volt power source that can be
switched on and off.
3. Be sure power source is switched OFF. Connect positive power source lead to red lead of solenoid. Connect
negative power source lead to solenoid body.
4. Turn power source ON and observe pin in center of solenoid. Pin should retract with power ON and return to its
original position with power OFF. Test several times to verify operation.
5. Make sure air cleaner element (including precleaner
if equipped) is clean and all air cleaner components
are fastened securely.
6. Make sure ignition system, governor system,
exhaust system, and throttle and choke controls are
operating properly.

Kohler Command CV25 Specifications

General

Brand	Kohler
Model	Command CV25
Category	Engine
Language	English