Mower crankcase filled with gasoline

[Oldtom]

Good Evening - I am trying to reanimate 2 riding mowers stored for years with a full tank of gas. One is Kohler powered and one is a Briggs. In both cases,the gas leaked into the oil and filled up the crankcase. Both mowers have a solenoid on the carb float bowl that should prevent this. I plan to install a fuel cutoff valve on each mower. Is this common? It seems the fuel leakage would be a fire hazard if the mower is stored in a garage.

Thank you in advance for any advice

 

[Merkava_4]

I can't see how the fuel would go into the crankcase unless the fuel tank is pressurized. Fluid always flows from high pressure to low pressure. The fuel tank is supposed to be vented to prevent this.

 

[eljefino]

I'd go through the carbs and make sure the needles and stuff seat properly. The solenoid's just a backup.

 

[Rand]

Probably a gravity feed gas tank.

Its high mounted under the hood right behind the "dash"
Extremely common on Briggs twin cylinder cheaper riding mowers.
Just install the Valve into the gas line 4$ and you can run the carb dry for storage.
Also check the exhaust bolts.. they always seem to loosen and even fall out on those engines.

 

[Eddie]

I've had that happen with gravity feed systems. I installed a manual gas shut-off between the tank and carb. Ed

 

[orcldba]

Very common with the gravity feed. It just takes a small amount of gunk on the carb needle and the crankcase will fill up: experience is not a wonderful thing!
Add a manual cut-off and a 150 micron filter, especially to the Kohler. That's what they spec and the 75 micron will starve the motor... Experience again!

 

[bubbatime]

Very common. Needle and seat gets gunked up, fuel continues to flow into engine and fill the crankcase with fuel. $3 shutoff valve in the fuel line "fixes" the problem.

 

[AnthemBassMan]

Also might as well just get a rebuild kit and clean out the carb. Carb rebuild kits should only run you around $5, $10 max. This happened to my 1992 Craftsman II mower with the Tecumseh 3.5hp engine on it. It drained into the crankcase and was leaking out from the air intake too. I had to buy the float separate, but I think I may have only had $10 total. This was about 6 years ago and hasn't happened again. That little bugger STILL starts up on the first pull!

L8R,
Matt