15 hp kohler

i got a 15 hp kohler moter on my mower and it runs good runs strong just wandering if there things i could do to get a bit more power out of it its all stock included the muffler maby file the jets a lil bit and run straight pipe just needing a few ideas thanks

I too dont know much about the engines. Now ofcouse I know basic and some advanced engine rebuilding, but Ive always been working with briggs..
I hope somebody can help us both on some details..maybe someone knows a link to some videos?

I do like the "carlike" filters and the carbs seem easy enough...mine also have a push-pull oil drain plug..I like the idea, but i may remove it.

I got them free, and I know why, I removed the spark plug to check for any compression, and they have a deep plug pocket, so I slide a 2 foot rod into the hole and I ended up pushing the piston back...and the crank had no movement....turned the flywheel by hand...no movement on the rod...and sure enough the flywheel came to abrupt stop..
So, for sure both engines have broke connecting rod assemblies..

So I will be pulling them apart soon...Please post with some guidance and IF anyone has some warnings or tips prior too...let me know!

How old of a kohler is it? Is it cast iron.

Its model is CV16S, not sure of the yr, Ill post full details once i get home, but from memory it is aluminum for sure.

goesman wrote:

How old of a kohler is it? Is it cast iron.

I have a 13 or 14 hp CVS and it is far more limited in overall mods one can do to it but there are a couple. A very mild porting of intake and exhaust is possible, and suggested if you have the skills. Kohlers of that kind are built to be almost as durable as their older counterparts (the K series etc) and not really known for flat out RPM or other such fun. BUT, with a mild porting (a stock one I THINK has 3/4" exhaust on anything bigger than 12hp) one can use a 1" exhaust adapted to the original flange and then a briggs type walbro aftermarket racing carb or something of the kind will actually bolt right on to the intake. If I recall correctly (it's been a while) the entire intake will interchange with a bit of tinkering on governor linkages and throttle linkages. That being said, a synthetic oil helps a ton for cooler running and a high-flow air filter will help it too.

With these motors for some reason they run even better with next to no backpressure unlike most of the small engines which always seem to want a little. Try to match the flow out, to the flow in. Takes some math, but well worth the effort.