+1 on JB weld will absolutely work in a pinch.

Back in 2009 a few friends and myself rode from VA to NC for the Smokeout chopper show. My friend Paul had just finished building his chopper and the mounting bungs on the bottom of his tank cracked spewing a couple gallons of gas all over his knees and hips.

We got a room for the night and showered up, he used some solo cups with the bottoms cut out to create a retaining ring of sorts, then poured the JB weld in and let it cure.

That tank held up fine all weekend, even for a few days when he got home. He then took it down and redid the whole tank. Point is it will work.

I'd clean the valve covers super well with some hot soapy water. Use some masking tape to build a sort of wall down both sides of the crack. Smudge the JB weld in and let it dry really well. Should be good to go.


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