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SharkD
02-13-2006, 02:09 PM
My mechanic and I are having a bear of a time trying to plug leaks on my newly-installed Accusump. The AN fittings on the hoses are sealing fine, but the NPT fittings between the valves and input adapters and the hoses are not.

He's tried the teflon tape and permatex teflon pipe thread paste independently and together to no avail.

Does anyone have any advice on what to try?

All of the fittings are quality parts, manufactured by Canton, Aeroquip and Earl's.

tgmeyer
02-13-2006, 03:19 PM
My mechanic and I are having a bear of a time trying to plug leaks on my newly-installed Accusump. The AN fittings on the hoses are sealing fine, but the NPT fittings between the valves and input adapters and the hoses are not.

He's tried the teflon tape and teflon pipe thread paste independently and together to no avail.

Does anyone have any advice on what to try?

All of the fittings are quality parts, manufactured by Canton, Aeroquip and Earl's.
I would use Form-A-Gasket for applications where there is contact w/ fuel or oil. Teflon, in my opinion, is for water jacket stuff.
Tom

SharkD
02-13-2006, 03:29 PM
The leaks are coming through the NPT threads on the (M) NPT-to-AN (M) adapter fittings on the Remote Oil Filter Mount and the remote oil filter adapter, as well as the (m) NPT-to-NPT (m) fitting that connects the accusump to the electric valve fitting. (The only NPT that isn't leaking is the 90° elbow M-to-F directly out of the accusump.

The AN-to-AN connections are holding tight.

The fittings are being tightened (on the bench) to the point where they will no longer turn.

Here is a PDF of the plumbing diagram (http://www.dvsmith.net/downloads/accusump-plumbing.pdf), and a picture of a similarly installed system (without the remote oil filter mount).


I would use Form-A-Gasket for applcitions where there is contact w/ fuel or oil. Teflon, in my opinion, is for water jacket stuff.
Tom

That may be what we try next -- or as one guy suggested on R3Vlimited, green loctite.

SharkD
02-13-2006, 04:02 PM
I'm juggling a bunch of threads going on a couple of boards... if you're curious about what others have said:

http://www.r3vlimited.com/board/showthread.php?p=429884

http://bimmerforums.com/forum/showthread.php?p=5904486

http://www.e30tech.com/forum/viewtopic.php?p=215588

http://spece30.northamericanbavarianracing.com/index.php?option=com_simpleboard&Itemid=65&func=view&id=2278&catid=5

tgmeyer
02-13-2006, 04:06 PM
The fittings are being tightened (on the bench) to the point where they will no longer turn.

Be careful! By design, the NPT seals b/c the thread is tapered. If you go too tight the female thread portion will split or strip. The sealant is just to fill in where the metal-to-metal contact is not perfect. I think you already know all this...