Kohler 10hp filling up with gas in the crankcase?

[stevebo-(Moderator) 8,409]

Guys,

I have a 1973 Case 210 garden tractor with a kohler 10hp. I rebuilt the carb and adjusted the float in just about the right setting (close anyhow). I cannot figure out why the crankcase is filling up with gas?? I figured that the needle valve was staying open or maybe the fuel pump is not right. I have a fuel pump coming that I won on epay. Anyone have this issue before and is there anything specific I should check?

[TT-(Moderator) 1,147]

Definitely sounds like a torn fuel pump diaphragm.

[stevebo-(Moderator) 8,409]

The funny thing this is just one of those machines that I have and do not use so it has not been on the top of my list until now. When you find yourself pushing these machines around the long back yard it makes sense to get them all in running condition. I replaced the pump once but I guess that one was bad too. I hope the new "used" pump will do the trick.

Will it leak by when not running if the diaphram is cut? I think the fuel tank is about even or slightly higher than the pump.

[TT-(Moderator) 1,147]

As long as the fuel level is higher than the pump, it can push fuel through into the crankcase.

[stevebo-(Moderator) 8,409]

Thanks TT. Hopefully this new pump will do the trick.

[TT-(Moderator) 1,147]

Actually - now that I think about the 210 that I had - the rear mounted tank might make it tougher for this condition to occur, but the recent higher temperatures (and perhaps a partially or fully clogged fuel cap vent) could result in pressure building in the tank.

Because the carburetor is that much higher than the tank, I can't see it pushing fuel in from there under normal conditions, but pressurize the system and that could change in a hurry.

I would still try a different pump first. :)

[Suburban 550 28]

Definitely sounds like a torn fuel pump diaphragm.

Steve, that's where I would say it's comin' from.