Small Engines (Lawn Mowers, etc.): 19.5 HP Briggs & Stratton Turbo Cool Gas Engine, briggs stratton, hp briggs

Question
John,

I ran a compression check after I received your advice.  One cylinder was 120 psi and the other was 130 psi which would indicate (at least to me) the rings are fine.  Is it possible the fuel could somehow be transferring from the carburetor to the crack case by the vacuum line that connects the two?  I appreciate your help.

-------------------------

Followup To

Question -
I have a craftman riding lawn mower (model 917.270913) with the 19.5 HP turbo cool engine.  I have not had any problems with the engine and it has run great until last week.  I was not able to start the mower after it sat for a couple of days. After a little trouble shooting, I found a significant amount of gas in the oil. I drained the oil, put in fresh oil, cleaned the plugs and it fired right up and ran great.  After about 2 minutes I started to see smoke from the exhaust.  After another two minutes (with the engine continuing to run) there was a sigificant amount of smoke coming from the exhaust.  I shut the engine down and checked the oil again. The oil was milky white from gas contamination. I would appreciate any advice you could provide.

Answer -
 Hello Jeff:

 From the Description of your problem it sounds like the rings have collapsed. They no longer expand with the engine as it heats up. My suggestion is to Overhaul the Engine and Rebuild the Carb.  Also install a Fuel Cutoff for when the Mower isnt in use. Hope this Helps.

 Good Luck

 Respectfully

 John

Answer
 Hello Jeff:

 Was this Compression Test done with the Engine Hot. The Compression can be Good when the Engine is Cold and Drop to Less than 70psi after it get to Operation Temperatures. There is only 3 ways for the Gas to get into the Crankcase. 1- Gas sits in the Cylinder and Leaks by the Rings. 2- Gas Bypasses the Rings under Conpression. 3- If someone pours it into the Crankcase. There is no other way for the Gas to enter the Crankcase. Hope this Helps.

 Good Luck

 Respectfully

 John