Pelican - fiberglass gas tank fitting + sealer

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JamesBurrett

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May 15, 2021
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hi - I have a 1986 Pelican Club with fabric wings. The previous owner disconnected the original fiberglass gas tank as there was a pinhole leak and removed the gas line.
There is a single unthreaded 1/2 inch hole into the bottom of the tank.
Does anyone have any suggestions as to how to connect a leak proof fitting?
I am thinking of a compression fitting where a rubber ring between two plates is expanded as the fitting is tightened. There is no access from the top side though,
Has anyone seen anything like this ?
Another idea is a pipe thread (slightly tapered) with gasket maker on the threads and then screwed in until sealed.
Also looking for recommended sealer for a fiberglass tank.
Any suggestions welcome.

thanks
James
 

rv7charlie

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This, plus this?
Those and similar products are common with rotomolded plastic tanks (including my zero-turn mower); might also work with fiberglass.

If you're halfway clever with a coat hangar, you can use something like this. Run the coat hangar wire so it extends out both the filler neck and the drain fitting, and drop the interior part along the wire. Note that the same type products are available from multiple sources; I just picked that one because it was easy to find in the moment.

A much higher hassle method is to bond an aluminum fitting to the fiberglass tank. (Would not be my 1st choice.)

For sealing: What are you sealing? If repairing the pinhole leak, epoxy would probably be the best choice. If you're sealing something to the tank, do some searching for 'Proseal' or Flamemaster fuel tank sealant. It's a polysulfide material that bonds well to aluminum and to fiberglass.

[edit to correct the link to the fuel tank bushing]
 
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Hot Wings

Grumpy Cynic
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Welcome to HBA.

A pic of the tank and surrounding area would help us give better suggestions.
"Rubber" covers many compounds. Some are suitable in contact with fuel and some won't last a day.
My first thought, presuming the pinhole leak has been repaired, would be to flox in a steel, not aluminum, pipe thread fitting made from hexagonal stock.
My second thought would be a rectangular* metal 'sandwich' riveted/bolted in place with ProSeal.

As rv7c* noted above a finger filter should be part of the project.

* can't get a round ring inside a hole of smaller diameter
 

rv7charlie

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Corrected the bushing link to show a more appropriate (ethanol resistant) bushing.
HW, you can, if you feed it through a larger hole. See the 'rest of the story' in my post.
And the rubber bushing/filter/valve combo is inserted from outside the tank.
 
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