shop-talk
[Top] [All Lists]

Sealing a gas tank?

To: shop-talk@autox.team.net
Subject: Sealing a gas tank?
From: Mike Lee <mikel@ichips.intel.com>
Date: Tue, 30 Jan 2007 16:46:42 -0800
I'm finishing up putting an old Suzuki motorcycle back together.  The original 
petcock on the gastank was corroded/seized up, and an original replacement was 
not readily available, so I bought a Pingel petcock and put it on.  Now, I 
can't get the tank to stop leaking at the petcock/tank interface.

The tank had an oval opening for the petcock, secured by two bolts.  The 
petcock was sealed to tank with an oval shaped (to match the petcock; the 
cross section is round).  The new petcock consists of a adaptor plate which is 
sealed to the tank with a fibrous gasket that is coated with hylomar; the 
petcock is threaded into the adaptor plate, and sealed with teflon tape.  The 
new petcock is larger in diameter than the original one, so the original 
opening was reamed larger; however, the adaptor plate does not center the 
petcock in the opening, so there is a fairly large section which is sealed 
only by the hylomar/gasket, and is not actually plugged by the petcock.  In 
addition, the adaptor plate and petcock have a tapered thread.  In order the 
have the outlets properly oriented on the bike, the petcock is not even finger 
tight on the adaptor; according to Pingel, the teflon tape should be 
sufficient to seal this.

So it seems there are 2 possible leakage points; I suspect both of them are 
leaking at least a little.  I'd like be able to put a better seal at both 
points, but would like at least one of them to removeable in case the tank 
needs to be cleaned out in the future.  I've tried up to 10 wraps of teflon 
tape, which leads me to think that I need something more substantial.  I'd 
tried rtv or something similar, but none of them have state that they are gas 
resistant.

Any suggestions appreciated!




<Prev in Thread] Current Thread [Next in Thread>