Squaring up plastic pipe fitting...

generator12

Senior Chief Petty Officer
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Jul 9, 2010
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Replaced the air bleeder on my well tank and having problems sealing it. It's a ,male 1 1/4 MPT fitting, some sort of plastic composite, as is the female on the tank. I snug it up to what feels like "tight" to me, but it continues to leak. In order to function, the device must be in one specific position, with the float working vertically. Thus I need one more full revolution.

I feel that if I try for one more revolution I'll strip either the tank fitting or the bleeder fitting. (And I sure don't want to replace the tank..!) I've tried normal pipe dope, and teflon tape (2 wraps one try, then 3 wraps on the second) but still get a small drip every five seconds. (About a pint every 24 hours..!)

Is this something that can be rectified by using a "correct" number of wraps with the tape? Is there a more viscous pipe dope that might do it? I can't use a hardening dope because of the likelihood of needing to replace the bleeder again in the future.

I'm no plumber and I'm hoping for suggestions.

Thanks guys.
 
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Redfred1

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Sep 23, 2013
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On my pressure (Bladder) I did not use glue; just tape. As far as glue; I use the purple. It has a slower cure time and gives me time to adjust.to the right position. The clear doesn't.
 

dingbat

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Go to a pool supplier and get a tube of fitting and gasket lube. Best plastic pipe and gasket sealer I’ve found.
 

generator12

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Dingbat, does that stuff stay soft, or does it dry hard? As mentioned, I'll need at some point to remove/replace this air bleeder.
 

bigdee

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Jul 27, 2006
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Teflon tape on plastic is a no/no. Sealant is what your supposed to use. Be careful over tightening tapered pipe threads on plastic. Because these fitting are made in a split mold there is a certain amount of flash on threads which can cause sealing problems. Loc-tite makes a sealant paste for plastic pipe that is no-hardening.
 
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Redfred1

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I said Tape because that's what was on the threads when I changed the tank. The Bladder had burst;and had no water pressure.All I had to do was disconnect a Union; unscrew the 1" elbow; retape and reassemble. Took longer for the water to drain.
 

dingbat

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Dingbat, does that stuff stay soft, or does it dry hard? As mentioned, I'll need at some point to remove/replace this air bleeder.
The stuff is a gel. It’s “tacky” when applied and stays that way.

I use it religiously on o-rings, gaskets and plastic pipe connects.

All bets are off if you damaged the thread on the plastic screwing it into metal. The only sure bet there is a new plastic fitting.
 

Redfred1

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Sep 23, 2013
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Might be some good stuff; might try it. Reading the Specs; it states it works on Gas fittings. Maybe liquid; but I would be leary of using it on natural or propane gas. The propane people gave me a tube of stuff they use. That is the good thing about propane; it has a smell you can detect.
 
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