Kohler Engine Blowing Smoke

I have a 10 Hp Kohler K241S that has started to burn almost as much oil as gasoline. I downloaded a service manual and measured the bore. The measurement (3.2580)is outside the limit of useful life for this engine according to the manual. Does that mean that even a set of oversized piston rings can't save this engine? It runs great (except for the smoke) and the cylinder walls have no scoring and the bore is uniform all the way around and from top to bottom. I do not know if this engine was ever re bored as I am at least the 3rd owner. I was told by one individual that oversized rings might do it, but that was before I made the measurements. If oversized rings will work, what size ring should be ordered?

 

Hello: WML13

To much oil. ??? If you recently added oil, recheck the level. Regardless as to your adding oil not recheck oil level on level ground before starting up engine.

Excessive oil will cause exhaust smoke while engine is running.

Also check engine breather. A plugged breather will allow engine intake vacuum to suck oil out of lower end and burn it.

Just a few often missed points as offered suggestions.

Most likely I haven't covered all of the possibilities. The resident small engine service and repair professionals in the forum may be able to offer additional suggestions, advice & help.

Check back on your question several times over the next few days for additional replies.

Regards & Good Luck. Sharp Advice.
25 year Vocational Small Engine Tech. Web Site Host, Forums Monitor and Multiple Topics Moderator.

 

Did the bore measure the same across the crank as it did parallel to the crank?

 

Good question... if the measurement is the same all around and all the way down,t hen it may be bored. Usually a bored engine will have an oversized piston that is stamped with the oversized amount on top of it. Most likely the engine can be saved, it's just a matter of whether you need to bore it or just re-ring it.

 

The bore measurement seems to be the same in all directions in relation to the crank from top to bottom. I do need to check breather now and find any marks in the piston. I will post back my findings.

Thanks!

 

Pop the top compression ring off the piston and put it in the bore of the cylinder, four sides equal distance down from the top edge and, using a feeler gauge measure the ring gap.

 

With some scrubbing I could see the top of piston. It has a .30 stamped into it. I also had so much dirt covering the crankcase breather that I couldn't see it. I don't have any slop in the pistion from trying to move it side to side. I think I will re assemble it and see it the clean breather changes anything.