Penton Owners Group

General Discussion => Penton Talk => Topic started by: Jim A on March 01, 2008, 06:13:57 AM

Title: Petcock question
Post by: Jim A on March 01, 2008, 06:13:57 AM
I have a '72 Berkshire and have coated the inside of the tank with the Caswell coating and installed new petcocks from Al B. There is a slight weeping on the threads, not a drip, just wet on the few threads above the mounted petcock. Using the search function Permatex #2 and Loctite PST have been mentioned. Do either of these solve the problem. I would like to get the tank professionally painted as the current paint is peeling in large sheets from leaks
before I bought it and I don't want to ruin a new paint job.
Any recommendations appreciated,
Regards,
        Jim

Jim A
Title: Petcock question
Post by: G Ellis on March 01, 2008, 09:31:14 AM
Jim  I put plumers tape on the threads of my tanks. Hope this will help. Later Gary
Title: Petcock question
Post by: 454MRW on March 01, 2008, 11:53:14 AM
Please correct me if I'm wrong, but I was under the impression that the gasket seals the flat bottom of the threaded insert of the tank against the top flat of the mating portion of the petcock, and if the gasket is sealing properly, there should not be any seepage into the threads to begin with. A little sealant on both sides of the gasket would help it seal. Mike

Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S
Title: Petcock question
Post by: thrownchain on March 01, 2008, 05:08:21 PM
Another thing, if you use sealent, make sure it's fully cured before you put gas to it.  Also do you have the gasket in place??
Title: Petcock question
Post by: Jim A on March 01, 2008, 06:52:49 PM
Thanks for the suggestions. The gaskets should be in place, I put the new reproduction petcocks on as they came but I'm not real familiar with this type. Only one petcock has the seep. It's the right hand side one, otherwise I would cap it off. I guess I could swap them and see how that works.
Regards,
        Jim

Jim A
Title: Petcock question
Post by: 454MRW on March 01, 2008, 07:08:19 PM
I would carefully inspect the flush end of the threaded insert in the tank for any nicks or the possibility of a crack. You can polish the end up with ScotchBrite or find emery paper taking care to do it evenly with a flat object to support it. Make sure that the threads on the insert on the tank are clean and unobstructed. I have even used a dab of Vaseline on the threads (or a tiny amount of lubricant that will not wick into the sealer if used), which will allow the petcock to compress the gasket without requiring excessive torque to accomplish it. Overtightening may cause the gasket to split. Mike

Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S