I have a 1986 4HP Mariner with integeral tank. The fuel switch appears to me to be very poorly designed, consisting of a rubber washer in an alloy casting and a piece of plastic that fits over the washer with a channel for the fuel inset. The whole set is tensioned by a nut and spring run through the washer from the plastic piece. The problem is the plastic piece rotates thro 90 degrees to switch the fuel on and off but if there is any lateral movement allows fuel to leak past, not good!!! If you tighten the tension device you can't turn the tap, also the nut on the back will slowly undo. The new tap is exactly the same so I'm no better of and somewhat poorer. Has anybody out there any decent solutions to this problem? I've tried a little grease on the washer but as its petrol based it dissolves and any effect is soon lost. Hopefully listening out. Thanks in advance.
