Yep. That's the leading suspect in my current carb issue of running too lean. Still haven't had a chance to replace it. I've never had it out, so I'm not too familiar with it other than what I've read about it.
I had two OEM pumps fail on my CH-25 in about 1300 hours. Each time it filled my crankcase with gas. Since the pump is integral to the valve cover, and not reparable, the replacement is about $125-150 (+/-). The second time, I replaced it with an electric, low-pressure, low volume pump for less than $50.
Kent, How do you check the fuel pump to know if for a fact that is how the gas is getting into the crankcase? And do you have any information on the electric pump that you installed.
Hey Kent, When you had your 425, did you ever try not using the fuel pump, straight line from tank to carb? Didn't know if the gravity would be enough and if the tractor would starve if was under a heavy load.
I don't know about Kent's setup (there's been several variations of 425s over the years), but on mine, only about 1/2 of the fuel in the tank sits above the level of the carb. Gravity will only feed down to about 1/2 a tank. His might be different.