http://www.thesamba.com/vw/forum/viewtopic.php?t=513681&postdays=0&postorder=asc&start=20
Also, both GoWesty and Van Cafe offer warnings regarding the tabs being funky.
I don't see how you could do this job without having some apparatus (rubber plugs & bicycle pump?) to do the pressure test; you sure don't want to be removing and installing the tank over and over again to find out the bad news.
The whole reason for me replacing the tank was engine bogging at high ambient temperatures and high altitudes; partially clogged 7mm outlet on 31 year old fuel tank was the suspect, now I've got a 12 mm outlet and a clean fuel tank, so hopefully no issues for another 31 years.
Thanks for everybody's help and suggestions. Just be forewarned and wary about defective fuel tanks if you do this job. The vendor was informed of the defect, but I made the decision to go ahead and try to work around it; a replacement tank would most likely have had the exact same defect and would have added another week or two to getting my van back on the road.
Rich
San Diego
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
To: vanagon@GERRY.VANAGON.COM
Sent: Wednesday, October 19, 2016 2:39 PM
Subject: Re: Fuel leaking from Sender Unit on Replacement Fuel Tank
Send the tank back as a defect. The hole is stamped wrong. The only way to get suppliers to own up and improve quality is to make them aware of the problems. I have yet to see a problem with the senders or the O-rings provided with them (or the tank). The tank cut out is slightly off center so the O-ring doesn't seal. You shouldn’t have to fight it and any type of sealant here is an experiment and future failure.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Richard Koerner
Sent: Wednesday, October 19, 2016 2:59 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Fuel leaking from Sender Unit on Replacement Fuel Tank
I recently replaced the Fuel Tank and the Sender Unit on my 85 Vanagon; I purchased these from Van Cafe and had my VW mechanic install. Initially had a BIG leak when filling up the tank. Mechanic dropped tank and spent time bending and adjusting the tabs that hold the Sender Unit to get a better fit with the o-ring, and used a straightedge to try for as flat a surface as possible. The leaking stopped (he pressure-tested and smoke tested)...but has now re-appeared when filling the gas tank to full.
It appears that MANY aftermarket tanks and Senders have this problem.
I'm thinking of applying some epoxy putty (gasoline resistant) when installing the Sender to fill the potential gaps of the mating surfaces. Maybe some of the epoxy between the mating surfaces, and then build up a fillet of epoxy around the perimeter of the Sender Unit?
Any advice on this issue? Van is currently over at mechanics....we are scratching our heads for a permanent solution.
Rich
San Diego