Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

I have an old Pincor generator that has a plastic gas tank.  I suspect it is made out of high density polyethylen (HDPE).  I need to seal the 1/8 NPT fuel shutoff into the tank.  The original shutoff valve had some type of glue sealing (and holding its orientation) in place.  I had to remove the old shutoff because it was rusted solid. 

I tried using a hardening teflon-based sealer (recommended by Permatex), but this doesn't hold the fitting still enough (when you open the shutoff, the fitting moves, then the cured sealer doesn't seal anymore).  Permatex doesn't recommend a sealer that stays soft (like their PST goo) or a teflon-based tape. 

Anyone have any success stories using JB Weld or something else available at an auto parts or hardware store? 

Whatever they used at Pincor back then really stuck to the plastic tank.  Unfortunately, Pincor has been out of business for years.  The local OPE guy says use teflon tape, but that won't do the job. 

My main concern is that the fitting can't rotate after curing.     Also, there isn't any way to mechanically secure the fuel line in place. 

Any help would be great.

Ralph S

I use 3m Marine adhesive sealant on lots of stuff. I like the 5200 fast cure. Not positive about the gasoline though. You will need to check. Both parts are NPT, correct? One is not NPS is it?

Seems like the plastic tank itself may not offer enough resistance... hold the shutoff with pliers / wrench when you open / close it...

Or... move the shutoff away fron the tank into the middle of the fuel hose line...

Dave...

I'm pretty sure both threads are NPT, as the original shutoff that came out was NPT.  Actually, I don't know what NPS is. 

I could put the shutoff in the line, but I'm still faced with the problem of securing a fitting into the tank. 

I am waiting for a reply from JB Weld.

Thanks for all your suggestions.

Ralph

There are different grades of 5200. But the "permanent"  is supposed to hold up to gas and oil. it's a polyurethane that cures with moisture .  Whether it sticks to the gas tank is another question, but it's mighty gooey. Get some alcohol to clean it off wet : grind it off after curing.

The tube will usully cure solid after a couple days after opeing. You might prolong it by putting it in the freezer.

Have you tried an epoxy like JB Weld?

NPT is tapered

NPS is straight

They might look the same, but they are not.

Maybe put the a fitting with the corecct size thread in the tank that has a hose barb on the other end.  Put a hose and clamp on the barb and route the hose where you can mount the shut off on a small bracket. Then run another piece of hose to the carb.

Or mont the shut off on the carb and just run the hose to the tank.