A Plastic Fuel Tank Miracle

Repair or modification of Boston Whaler boats, their engines, trailers, and gear
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Joined: Mon Jan 11, 2016 12:46 pm

A Plastic Fuel Tank Miracle

Postby steelhead55 » Tue Apr 03, 2018 1:14 pm

A tank miracle happened on my current project of tank repair for my 1979 V22 Revenge. A member here had stated that when he had a 1979 Revenge plastic fuel tank replaced by the factory with an aluminum tank, he watched his plastic tank that was sitting in the sun regain its shape. My boat's fuel tank shape was lousy, and I had very little hope it would roll back into shape with just a little bit warmth. See pictures in links below.


While I was visiting my girlfriend in San Diego this weekend (which was warm, almost 80 degrees at home each day), I returned home to see my tank looking like this:


The tank is now back to its original shape with just a little warmth. I am now convinced that simply the constant force of the incompressible (15 gallons of) water that was beneath the tank, trapped in the tank cavity, forced up the bottom of the tank over time. To remedy this I am in the process of installing a drain tube from the tank cavity to the fish locker so that water can be removed from the bottom of the tank. I will post pics of the final tank set up after installation.

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Don McIntyre - MI
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Joined: Fri Oct 09, 2015 4:33 pm

Re: A Boston Whaler plastic tank miracle

Postby Don McIntyre - MI » Tue Apr 03, 2018 1:44 pm

As I mentioned in the prior discussion, Boston Whaler told me that [deformation of the plastic fuel tank was caused from] the hull freezing. Water that had migrated past the foam due to the mold release agent not allowing for the foam to adhere to the tank, pooled in the space between the bottom of the tank cavity and the tank.

Was your vessel ever stored either outside or in an unheated storage shed in the winter?

For the first two years we owned the Outrage 22 it was stored in a heated building. The following year, unheated building. That summer was when the problem cropped up.

Regards - Don

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Joined: Fri Oct 16, 2015 3:23 pm

Re: A Plastic Fuel Tank Miracle

Postby kwik_wurk » Fri Apr 13, 2018 3:30 pm

Keep the girlfriend. Maybe the tank will re-install itself, too.