Leaking fuel pump seal

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Bandit Greg

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Jan 3, 2022
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Location
Lower Hudson Valley, NY State USA
Hey guys...
I'm going bonkers trying to get a good seal between my fuel pump and the bottom of the tank on my 2nd Gen FJR.
I bought the bike a couple of years ago, and kept smelling fuel faintly, which I just figured was from venting until one day I noticed there was residue on the heat shield, in that little pocket under the fuel pump.
Since then I have had the fuel pump off the tank no less than six times. I've tried everything I can think of, from replacing the gasket, (twice with a new OEM item and once with a perfectly-fitting O-ring).. to sanding the sheet metal mating surface... very gently tapping any flatness issues out.. inspecting the fuel pump for cracks repeatedly. I've tried three different types of sealant (all fuel-safe)... I even ground a millimeter off the aluminum flange thickness to get a snugger fit.
It still weeps. No major DRIPS particularly, just enough to spot a paper towel overnight.
So the one question that's been on my mind is the gasket positioning.
Does anyone have direct knowledge of whether the FLAT side of the gasket goes against the tank metal.. or against the fuel pump groove? Neither of my manuals show this, nor does the parts fische.
OUCH this wearing me down!
 

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I tend to have the same thoughts as Ross....overtightening is a sure bet for a leak. Are the bolt holes blind, or do they go into the tank? Sealant on the bolts?
 
I just went through this this past summer. After talking with fuel injector services and various other places the rule of thumb is that the flat side faces away from the fuel. I installed mine that way and it has been leak free.
Hey guys...
I'm going bonkers trying to get a good seal between my fuel pump and the bottom of the tank on my 2nd Gen FJR.
I bought the bike a couple of years ago, and kept smelling fuel faintly, which I just figured was from venting until one day I noticed there was residue on the heat shield, in that little pocket under the fuel pump.
Since then I have had the fuel pump off the tank no less than six times. I've tried everything I can think of, from replacing the gasket, (twice with a new OEM item and once with a perfectly-fitting O-ring).. to sanding the sheet metal mating surface... very gently tapping any flatness issues out.. inspecting the fuel pump for cracks repeatedly. I've tried three different types of sealant (all fuel-safe)... I even ground a millimeter off the aluminum flange thickness to get a snugger fit.
It still weeps. No major DRIPS particularly, just enough to spot a paper towel overnight.
So the one question that's been on my mind is the gasket positioning.
Does anyone have direct knowledge of whether the FLAT side of the gasket goes against the tank metal.. or against the fuel pump groove? Neither of my manuals show this, nor does the parts fische.
OUCH this wearing me down!
 
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