Expert: John C. Bridgers Sr. - 7/3/2007

Question
QUESTION: I have a kohler command 25hp motor with an external oil cooler.  One of the hoses broke today and the oil leaked out of the engine and the driver didn't notice until the engine died from no power.  After letting it cool for about an hour I replaced the hose, put fresh oil in it and started it up. It runs but was lacking power. I pulled off the left spark plug wire while it was running and the engince died.  I put it back, started it up and removed the right spark plug wire and their was no change in the engine.  I pulled the spark plug on that side to check for spark and there is spark.  I checked the lifters on both sides and appear to operate normal.  Any ideas????

ANSWER: Hello Tom:

Send me the Model Numbers Off the Engine, Please. With these I can Locate the Proper Manual and Better Assist you. However, Check the Cylinder Compression. If the Compression is Below 75PSI then, Remove the Cylinder Head and Check the Cylinder for a Gouge or Scarring in the Cylinder. Check for a Blown Head Gasket. If the Compression is Good, then Check the Valve Clearance. .003in - .005in Intake and .080in - .010in Exhaust. The OEM Suggest .004in on Both the Intake and Exhaust. I Do Not Use those Becaus of Burning the Exhaust Valve and I have Less Starting Problems. Hope this Helps. I am Here if You Require More Assistance. Let me Know What Happens, Please. Thanks.

Good Luck

Respectfully

John

PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting you Question at or Just After 9pm EST (US). My New Day Starts then. Thanks.

Respectfully

John

---------- FOLLOW-UP ----------

QUESTION: The motor is a ch25 68544.  Is that what you need?  I don't have any way to check compression.  Is that something you can buy inexpensively at an auto parts store?  It has hydraulic valves so I did not think you could adjust them.  I do know how to pull the heads so I guess I can do that and check for scarring.

Answer
Hello Again Tom:

I Suggested the Valves because Some of the Engine Models have Solid Lifters (Tappets)Depending on the Model. I Wanted to Give you  Some Starting Points in Case you had Trouble Getting Back to me. Check the Cylinder and Head Gasket. If these Are Good, then you can Purchase an Inexpensive Compression Tester for Approximately $30.00 Dollars (US) or Less. If the Compression is Above 75psi, then the Rings are Good and you need to Start the Engine and Spray some WD 40 Around the Intake Connections at the Cylinder Head and Along the Intake Housing. If the Cylinder Starts Firing, then the Point where the WD 40 was Being Sprayed is Causing a Vacuum Leak and the Cylinder Can Not Draw Gas to Fire. You can View a Breakdown/IPL of this Engine at this Site Addy, http://www.smallenginepartswarehouse.com/parts.asp and Select the Shop Online Parts Look Up. Then Select the Model Tab. Then Select the OEM and Enter the Model Numbers. Then Double Click on the Model in the Results Area. Now you can Select the Section of the Engine you Wish to View. Hope this Helps. I am Here if You Require More Assistance. Let me Know What Happens, Please. Thanks.

Good Luck

Respectfully

John