How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Wayne Your Own Question
Wayne, Engine Rebuilder
Category: Small Engine
Satisfied Customers: 8460
Experience:  many years on egine rebuilding, lawn mower,roto tiller,Truck,and small engines
Type Your Small Engine Question Here...
Wayne is online now
A new question is answered every 9 seconds

I have a Kohler CH25S 68515 engine with about 490 hours. No

Customer Question

I have a Kohler CH25S 68515 engine with about 490 hours. No oil or smoking problems. Engine ran fine for the first 6 or 7 years. Then I started having problems with the engine running rough for a few minute to up to 30 minutes. Several small engine mechanics have gone over the unit with little success. It is on a 97 Bunton mower and they have little to no support in my area, but Kohler is a popular unit. Two years ago I replaced the carburetor and the engine went to running like new, then the problem returned. Have tried numerous fuel types. Soaking and cleaning the old and new carburetor. Unit will run fine for a short time then start running rough again. Filters changed, plugs changed, tank flushed new fuel pump and lines even the electronic ignition was replaced. Due to when this engine was designed is it more susceptible to problems related to ethanol fuel. The additives have had no effect. Have gone to using aviation fuel. Ideas???
Submitted: 1 year ago.
Category: Small Engine
Customer: replied 1 year ago.
(Posted by JustAnswer at customer's request) Hello. I would like to request the following Expert Service(s) from you: Live Phone Call. Let me know if you need more information, or send me the service offer(s) so we can proceed.
Customer: replied 1 year ago.
Call me on 6/27 at 9:00 am EST. What should be done to repair the engine. Is Kohler aware of issues with this engine and Ethanol fuel.
Expert:  Wayne replied 1 year ago.
Hi I'm Wayne I will help you with this you mentioned every thing that makes sense, but you never mention valve adjustmentthis needs to be done, every 400 hours , or you will have problems, I suggest to adjust the valves, If this helped you, Please rate my answer3 stars or higher this is the only way I get credit for the questionIf not, please reply for more infoThank you
Expert:  Wayne replied 1 year ago.
I'm Just following up with you
did my answer help you
let me know

Related Small Engine Questions