Troubleshooting
Do not attempt to service or replace major engine components, or any items that require special
timing or adjustment procedures. This work should be performed by a Kohler authorized dealer.
Problem
Will Not Start
Hard Starting
Stops Suddenly
Lacks Power
Operates Erratically
Knocks or Pings
Skips or Misfi res
Backfi res
Overheats
High Fuel
Consumption
Engine Specifi cations
Model
Bore
CH621
CV621
3.03 in.
(77 mm)
CH641
CV641
CH620
CV620
CH640
CV640
3.2 in.
(80 mm)
CH23/CH680
CH670
CV23/CV680
CV670
CH730
CV730
CH740
3.27 in.
(83 mm)
CV740
CH750
CV750
*Exceeding maximum angle of operation may cause engine damage from insuffi cient lubrication.
Additional specifi cation information can be found in service manual at KohlerEngines.com.
Exhaust Emission Control System for models CH23, CV23, CH620-CH740, CV620-CV740,
CH750, and CV750 is EM for U.S. EPA, California, and Europe.
Any and all horsepower (hp) references by Kohler are Certifi ed Power Ratings and per SAE J1940
& J1995 hp standards. Details on Certifi ed Power Ratings can be found at KohlerEngines.com.
8
Dirt In
No
Improper
Fuel
Fuel
Fuel
Line
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
Stroke Displacement
38.1 cu. in.
(624 cc)
41 cu. in.
2.6 in.
(674 cc)
(67 mm)
44.2 cu. in.
(725 cc)
2.72 in.
45.6 cu. in.
(69 mm)
(747 cc)
KohlerEngines.com
Possible Cause
Dirty
Debris
Incorrect
Screen
Oil Level
Overloaded
●
●
●
●
●
●
●
●
●
●
●
Oil Capacity
(Refi ll)
1.7-1.9 U.S. qt.
(1.6-1.8 L)
Engine
Dirty Air
Cleaner
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
Maximum Angle
Spark
of Operation
Plug Gap
(@ full oil level)*
0.03 in.
25°
(0.76 mm)
24 590 43 Rev. --
Faulty
Spark
Plug
●
●
●
●
●
●
●
●
●