Regular lube oil in top end of KTM 495 2 stroke

[Olmy]

I recently bought a 495 engine off a guy.  He had it stored in his garage for years.  Every now and then he would squirt some 3 in 1 oil into the cylinder to keep it from rusting.  When I got the engine and did a quick look over I found that the engine has never been torn down.  I started it after having to flush the engine out with gasoline.  After it started it poured out thick heavy white smoke.  I shut it down after about 5 minutes of running.

My question is will this oil that the guy put into this cylinder create hot spots in the cylinder or piston creating quicker breakdown of parts if I just let it go.  Or should I pull off the top end and clean it up real good removing the oil?



 

[Larry Perkins]

I would think any oil that was in crankcase area would be gone by the time the bike ran 5 minutes.  There should be no great damage from the oil residue.  I suspect you have a clutchside crank seal sucking in tranny fluid.  Crank seals often go bad in bikes that sat around a lot over many years.  If gas is good and jetting relatively close it should not smoke a lot.