best diesel-resistant sealant for fuel sender

[rmwac]

Hi: My first post ... I have to replace an old fuel sender in my Newport 27 diesel tank. The original had what appears to be a leather gasket, and it leaked every time the boat was heeled.... the main filler and fuel line/returns are in good shape. I have a new Moeler unit along with it's gasket. My tank is the plastic variety. The original mounting holes in the tank are stripped, but I might get away with using a wider screw with a coarser thread. I'd like to use an adhesive sealant in addition to (or instead of?) the rubber gasket. My fear for the rubber gasket alone is that I may NOT be able to tighten up the screws sufficiently to get a bombproof seal without restripping the holes in the flimsy plastic. I have plenty 3M 5200 on hand, and it is supposed to be diesel resistant, but what would you recommend? Once done, I never want to visit this assembly again!! Your ideas on prepping the plastic tank for adhesion are also appreciated. Thanks RON W

 

[bria46]

If you use 5200 you will never be able to remove the fuel sender that you install. Then when it goes bad forget it, you will never get it out using 5200.

 

[Kettlewell]

This Permatex has worked for me.

 

[Allan12210]

You could look into a threaded insert to repair the screw holes. Then look for a Permatex product that remains flexible but is diesel resistant. None come to mind at the moment, but should be searchable. If you want a flexible gasket material, I would look for either Viton or even Silicone sheet that you can cut to size.

 

[Allan12210]

Wow, Kettlewell you are fast!

 

[Kettlewell]

I should have added that the Permatex 2 blue is not really an adhesive--only a sealant. You really need to tap those holes out slightly, or I hate to say it just use some self-tapping screws.

 

[Steve Dion]

If that is a poly tank, not much is going to stick to it (even 5200). I would think that the Permatex poduct would be a good bet.

There is also one of those metal rings that allow the fittings to be thru bolted.
http://www.seabuilt.com/

I would think that this along with a proper gasket for diesel would do the job.

 

[Richard Bryer]

I used a Permatex product that looks very much like that when I sealed the cover on the cleaning port I cut in my fuel tank 5 years ago. No problem with it at all. The tube said resistant to kerosene which was the closest I could find

 

[MICHAEL7914]

never use silicon or similar on fuel parts...i sealed my sender with silicon...when replacing the 8 x8ba screws which hold down sender the silicon balls up on end of screws..diesel washes this off in form of small balls of silicon..these fly up your pick uppipe to the filter and may or maynot pass thru the small holes in filter housing...anyway when one is big enough it stops up the hole...engine stops ...ball no longer under suction falls out and motor starts and runs great until pick up picks up another silicon ball always use proper gaskets leather rubber cardboard anything is better than tube gasket on this part