TheFlyingScott

I just installed a SlickStart in my M20C and it made all the difference in the world! Instead of cranking hoping the engine catches before the battery runs down, she starts in two blades every time ! No muss, no fuss, just Bam and away you go

Well I checked the fuel tank vent line and found no blockage, at least as far back as I could push the wire. But the fuel transfer has stopped since I set the fuel selector to the OFF position.

With the amount of fuel missing from the left tank (gallons) I would imagine it would leave a telltale stain if it was a leak from the tank or the fuel selector, as I said there is no indication at all of a leak, no weep, no seep, no stain in wheel well, nothing on top of wing, nothing on bottom of wing. There is a noticeable stain on the tarmac under the right tank fuel vent but nothing under the left tank fuel vent. So I'm going to go on the assumption that the left tank vent is plugged causing the left tank to pressurize and force fuel through the fuel selector into the right tank. Good news is, no fuel tank leaks, of course the blocked vent is not good, I'll check it out when I get out to the airfield shortly. Thanks for the input guys.

It was parked outside but both wings got equal amount of sun. My suspicion is that the rubber/silicon seals (if there are any) in the fuel selector are failing and need to be replaced. No signs of fuel leakage under where fuel valve is, no signs of leakage under wings where fuel tanks are.

Hi Guys I recently purchased a 1976 M20F pretty much in stock condition. It had sat without flying for 5 years. I did pre-purchase inspection and everything checked out pretty much as expected. My problem is, it appears my left fuel tank is cross feeding into my right tank! I know this should be impossible since there is no direct connection between the two tanks except through the fuel selector valve. The fuel selector valve is suppose to connect one tank at a time to the engine. Last time i filled both tanks I left about an inch below the rim to allow for expansion. When I came back the next day during the preflight walk around when I inspected the tanks visually I found the left tank down a couple of inches and the right tank full to top and leaking fuel from the vent line. I guess my question is, is it possible that the fuel selector valve is not sealing properly and allowing fuel to flow from one tank to the other? I set the fuel selector valve to OFF this time to see if the problem persists (I haven't checked yet). Michelle N6987V