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Discussion Starter · #1 ·
Hello everyone, this is my first post on this site. My issue today is this:

I have a 38" simplicity with a 15.5hp briggs single cylinder ohv engine. The problem it has is that it burns oil/gas. There is gas in the oil as well. I researched this and several people said the carb was trashed and needed rebuilt, so, I installed a brand new one. This has still not solved the problem. I popped the head off, replaced the head gasket, adjusted the valves, and compression tested it (110lbs). It still burns a lot of blue smoke from the exhaust, as well as the crank case breather that leads into the airbox. Any ideas what to do now? Thanks!!
 

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:welcome: to MLMF!

From what you describe and have already done, it sounds like the piston rings are worn and that it's getting blow by. Typically this is a sign of a well used engine that could use a rebuild.

If you plan to continue using the machine as-is you can try running a slightly thicker oil although I wouldn't go too overboard with a much thicker viscosity.
 

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The compression does sound on the high end, but from you describe at least it points to the rings imo.

Perhaps others will chime in with some other ideas.
 

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Another point of entry for gas getting into the crankcase could be a vacuum operated fuel pump if it is so equipped.
 

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Discussion Starter · #7 ·
I have checke for gas overflow and theres no problems there. Just changed the oil and there was a lot of gas in it, it smokes like a banshee when under a load (pto engaged) but doesn't smoke when just idling
 
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