When to replace under deck fuel tank

panamacitymustang

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Hi I'm rebuilding my 91 regal velocity and was wondering if I should replace the gas tank. It looks fine. A little surface corrosion on top. I did wash and degrease it and covered the tank in epoxy. Now I'm having second thoughts since it's over 20yrs old. Any thoughts would be appreciated.
 

panamacitymustang

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Re: When to replace under deck fuel tank

Thanks for all that info. Now the question what tank to replace it with. Is there a certain brand to stay away from.
 

redneck joe

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Re: When to replace under deck fuel tank


this is scary as hell

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panamacitymustang

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Re: When to replace under deck fuel tank

Wow that is scary. A leaking gas tank is a bomb just waiting to go off. Mine don't leak. I just want to replace it since my floor is torn up already.
 

DeepBlue2010

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Re: When to replace under deck fuel tank

You are doing the right thing. 20+ years old fuel tank is trouble waiting to happen. Even if it is not leaking now, you don't want it to start after you glassed your new deck in. Did you decide if you want to go with Aluminum or Plastic?
 

tpenfield

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Re: When to replace under deck fuel tank

I replaced the tank on my 1991 Formula, because it was showing about a dozen deep pits in the aft face of the tank. So, it is a judgement call, based on the condition of the tank as you inspect it.

Although the tank on my boat was not leaking, the depth and number of the pits swayed me towards getting a new tank. If your fuel tank is in good condition with only minimal signs of corrosion, then it is probably a reasonable judgement to continue to use it. As a tank ages, the frequency of inspection should increase.
 

panamacitymustang

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Re: When to replace under deck fuel tank

Moeller Belly Fuel Tank, 52 gal., 24"W x 60"L x 10"D
Item # 30458

I'm thinking of getting this tank. I would love to use the tank I have but I just don't want to have to pull up the floor again. I just have to check the measurements of my other tank. Is plastic a good idea.
 

tpenfield

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Re: When to replace under deck fuel tank

I considered going with a plastic tank for cost reasons, but was concerned about the potential for the plastic tank to eventually have a fuel smell to it. So, something to consider. . . Would the tank eventually have a slight fuel smell to it?
 

panamacitymustang

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Re: When to replace under deck fuel tank

I read that somewhere also. But why would you smell gas if the tank is sealed.
 

panamacitymustang

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Re: When to replace under deck fuel tank

Can anyone shine some light the gas smell from a plastic tank.
 

81_chapparel194

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Re: When to replace under deck fuel tank

Can anyone shine some light the gas smell from a plastic tank.

because of permeation which is the evaporation (so to speak) of the fuel through the plastic and after time the fuel finally makes its way to the surface of the tank. not that its leaking but you can smell the fuel from permeation. this is supposedly the reason that the red outboard plastic tanks changed their formulation a couple of years ago, to reduce the permeation rate. hope this helps.
 

tazrig

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Re: When to replace under deck fuel tank

Metal Tank
 

jbcurt00

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Re: When to replace under deck fuel tank

Be sure to follow the maker's installation instructions. Plastic tanks will expand & contract a bit, there should be some details listed in the installation info.

Like Moeller's

2-3% expansion, in each of 3 dimensions.

24" wide tank then needs a 24 5/8" space, that's a 5/16" gap at either side of the 24" direction.
 
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