SL/R107: Leaking Fuel Pump - Any Ideas?
Thread Starter
Junior Member
Joined: Aug 2009
Posts: 25
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From: Canton, OH
2014 Audi Q7 SUV
Leaking Fuel Pump - Any Ideas?
Had my 1975 350SL in the body shop for the past 3.5 years and yes, the shop finally got it repainted. But now, after sitting for so long, the fuel pump is leaking gas out of its casing. Connecting hoses are fine, have been replaced, and are not leaking. Since the pre-1976 pump is very expensive new, I found a used pump in a local boneyard and installed it. Unfortunately it leaks, too, but this one leaks only when the engine is operating, not when the engine is off. Are these pumps rebuildable, or is there possibly something that is causing the pump to have excessive pressure and leak? The engine runs fine but the pump drips about a drop every 5 seconds onto my driveway. Changing the fuel filter does not affect the drip. I really don't want to spend $700 for a new pump . . . . especially if the real problem is something different - maybe a stuck pump relay causing excessive pressure . . . help! 
