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Having a hard time searching the site for what I need... Looking for gas proof/resistant sealant to keep the OEM fuel pump seal from leaking on my [new-used] IMS tank.

2009 450R... Bought a used IMS 3.2 gal, and a [new] mounting kit from IMS (w/ new O-ring that replaces the two OEM ones).

It leaks!

So I sanded a bit with 220 grit, cleaned with alcohol, and used some fuel resistant Permatex (#2 non hardening) in addition to the new O-ring. After almost 24 hours cure time, it only held for less than an hour, and yes I torqued everything correctly...

The #1 Permatex is permanent, so I'm reluctant to go that route as I'd never get the fuel pump off if I needed to.

Anybody have any fixes or experience with this? Thanks!

Hello, I have a couple suggestions. First a very, very close inspection to the area while it is leaking and after for a crack. It is often really hard to see and watch for the tracking of where actually any leak is originating from but easy to make assumptions. Light dusting of talcum powder is a good way to see where a leak is originating. Plastic tanks cracks are common especially with the ethanol in fuels. It dries out rubber and plastic horribly fast.
Second if you are absolutely 100% sure there is no crack then I recommend calling IMS and talking with them.
Now for your sealant. I do not think there is going to be any sealant that is going "fix" a leaking area on plastic. Coming from the aerospace world I have not ever seen any such sealant. O-rings are not going to work with anything on them. That is that entire design is to have total contact of the o-ring to the seal area with nothing interfering with the contact area.

Not much good news for you but a couple ideas for you.

Thank you for the reply..

The talcum powder is a good idea, I'll go try it. Going to lap the brass mounts while I'm at it just to be sure of flatness. And IMS did offer a trade-in deal of $200, so I may just go that route if I can't figure something myself. A little frustrating and my ego doesn't want to give up on fixing it quite yet.

You know what else comes to mind is that maybe it's the brass bosses themselves ? If you can come up with a way to pressure check without the petcock on it might be spotted ? If it was one of the bosses that could be epoxied back in to seal it.

Good luck & let us know what you find. Really has my curiosity going. '