Small Engines (Lawn Mowers, etc.): Kohler engine uses oil, blown head gasket, oil viscosity

Question
I have a Scotts(John Deere)S2554 Graden Tractor with a Kohler CV25S engine.  The engine has almost 500 hours.  It uses oil when it never did before.  After I change the oil in the spring I was always good for the season.  Last year and especially this year it is using oil.  I notice white smoke on start up with the choke.  Once it is running with the choke off I do not notice any smoke but I assume it consumes oil.  I had to add almost a quart this year.  Where would you look first to resolve this issue?

Thanks!

Kevin

Answer
I checked the service manual for your engine:

Engine Uses Excessive Amount of Oil
1. Incorrect oil viscosity/type.
2. Clogged or improperly assembled breather.
3. Breather reed broken.
4. Worn or broken piston rings.
5. Worn cylinder bore.
6. Worn valve stems/valve guides.
7. Crankcase overfilled.
8. Blown head gasket/overheated.

Service manual link:

http://www.kohlerengines.com/onlinecatalog/pdf/tp_2450_c.pdf

Have you checked the Crankcase Vacuum following the procedure outlined in the service manual?

Eric