How to seal diesel level gauge?

[suiramor]

I have replaced a faulty diesel tank gauge with a new (mechanical) one. It attaches with 5 screws to the top of the tank. It came with a rubber seal. However, in heavier seas, the pressure of fuel in the tank pushes some fuel out through the seal. It is particularly a problem when the tank is full. What material should I use to get tighter and reliable sealing?

[Pandor]

I just recently replaced my fuel sender with something that sounds identical. Mine was VDO Atlas. And I had some similar leakage after the install. At first, I was thinking of replacing the tapped slotted screws with some hex head screws. But in the end, I used a screw bit with my socket wrench and I tightened it up enough that it doesn’t seem to leak anymore.

[JoeRobertJr]

When I added a level sender, I was advised to use the orange Permatex 85420 Fuel Resistant Gasket Dressing & Sealant.

https://www.amazon.com/Permatex-85420

[suiramor]

Thanks JoeRobertJr. I will try that.
Thanks for responding Pandor. I somehow do not think the leak is on the screws but rather between the surface of the gauge and the top of the tank - there was just too much fuel leaking for the relatively small screw holes. Anyway, perhaps the sealant will do the job in both places.
Thanks again.

[GordMay]

Originally Posted by suiramor

Thanks JoeRobertJr. I will try that.
Thanks for responding Pandor. I somehow do not think the leak is on the screws but rather between the surface of the gauge and the top of the tank - there was just too much fuel leaking for the relatively small screw holes. Anyway, perhaps the sealant will do the job in both places.
Thanks again.

You, probably, over-tightened the screws - a very common mistake.