What Thread Sealant for White Plastic Pipe?

[CrispyCringle]

My grey water pipe has a seep. There are two white T-fittings about 1.5" ID on the main drain to the sump for grey water and they are joined by a grey plastic threaded coupling. And these joined T's have a threaded coupling on each end that goes to the main drain hose. Ive got a leak because the threaded part is pretty loose in one place.

I can see it was assembled with a yellow or old a darkened white thread dope. I was going to disassemble and clean it up and reassemble. What is the proper thread dope for this?

Thanks!

[wholybee]

Many dopes will work on almost anything.
https://www.amazon.com/76001-Blue-Mo...PR/ref=sr_1_19

[thinwater]

If it is loose, the pipe is not fitted properly and no dope will fix it. The threads must be properly cut and clean (wire brush helps). Also, confirm that the thread match and are all the same taper (they may be straight threads). Be careful not to over tighten plastic; the threads can strip.



If properly fitted, any name brand pipe sealant will work fine.

[CrispyCringle]

I’m guess the issue, when installed, was trying to get the pipes tight while at the same time having the T’s oriented the way they need to go. It’s been fine for over 12 years though.

Thanks for the sealer advice.

[mvweebles]

Rectorseal 5. If the threads can't be sealed with Rectorseal, they can't be sealed.

Available in all big box stores.

[Jim Cate]

Originally Posted by mvweebles

Rectorseal 5. If the threads can't be sealed with Rectorseal, they can't be sealed.

Available in all big box stores.

Are you sure that stuff is for pipes? sounds more like a diarrhea cure to me!

(Just kidding, ya know)

Jim

[Don C L]

Originally Posted by Jim Cate

Are you sure that stuff is for pipes? sounds more like a diarrhea cure to me!

(Just kidding, ya know)

Jim

Yeah that's pretty much what we called it when I used to work in construction.

[Wotname]

Originally Posted by CrispyCringle

I’m guess the issue, when installed, was trying to get the pipes tight while at the same time having the T’s oriented the way they need to go. It’s been fine for over 12 years though.

Thanks for the sealer advice.

Pretty hard to beat Loctite 55. No cure time required, easy to use and allows for 90 degrees of realignment after initial tightening. Good for plastic and metal threads and especially for damaged threads. Do not confuse it for PTFE tape.
https://docs.rs-online.com/782b/0900766b814bd9d1.pdf

[GordMay]

"Plastic" isn't a very good description, of your pipe and fittings. It could describe, either, PVC or ABS Plumbing pipe, or PVC electrical conduit.

Polyvinyl chloride [PVC] is commonly used in plumbing pipes/fittings, where it is often white, and electrical conduits/fittings, where it is often grey.
PVC plumbing pipes are pressure tested/rated, and PVC conduit isn’t.

PVC plumbing pipe [& fittings] can be either white [schedule 40], or grey [schedule 80] PVC; or grey/black Acrylonitrile Butadiene Styrene [ABS].

ABS can be connected using one cementing compound, whereas PVC requires a two-stage connecting process, using a [purple] primer, and then a solvent cementing compound.

[mvweebles]

Originally Posted by Jim Cate

Are you sure that stuff is for pipes? sounds more like a diarrhea cure to me!

(Just kidding, ya know)

Jim

Not the name I would have chosen. But I gotta tell you, the stuff works really well. I put on the threads of the deck fills of my diesel tanks that are on the side decks. Water intrusion through deck fills is a major vulnerability for boats especially powerboats.

[GordMay]

Originally Posted by mvweebles

Rectorseal 5. If the threads can't be sealed with Rectorseal, they can't be sealed.
Available in all big box stores.

RectorSeal No. 5:
For pipe made of galvanized steel, iron, brass, copper, aluminum, stainless steel, polyethylene, reinforced fiberglass, and PVC.
DO NOT USE ON ABS OR CPVC.
➥ https://rectorseal.com/rectorseal-no-5-group/
➥ https://cdn1-originals.webdamdb.com/...ASI2IOLRFF2RHA

[NorthCoastJoe]

Teflon tape comes in wide rolls for larger pipe. I would go with that wrapping 8 to 10 wraps if the pipe is loose. I have used it working on water well piping with no problems for years.

[CrispyCringle]

Here is what Im dealing with. Proved to be the obligatory PITA to remove. Looks like its nylon. Slick and fairly soft. Ill see how easy it is to clean up. Too much of a pain and Ill just get new fittings. I hate having all those joints. Only thing I can think to do is use a couple of Y connectors. But trying to find them and all the adaptors will probably not be worth the time.

[Wotname]

Originally Posted by CrispyCringle

Here is what Im dealing with. Proved to be the obligatory PITA to remove. Looks like its nylon. Slick and fairly soft. Ill see how easy it is to clean up. Too much of a pain and Ill just get new fittings. I hate having all those joints. Only thing I can think to do is use a couple of Y connectors. But trying to find them and all the adaptors will probably not be worth the time.

This is the perfect situation for Loctite 55.
- Allows for precise angular positioning without the problem of over/under torqued threads.
- Quick, easy and clean application.
- Easy and clean disassembly.
- It is suitable for all types of 'plastic threads', no need to determine type of plastic.
- Easier (and better) than PTFE tapes. Easier to apply than most (all?) dopes.
- Zero cure time required.

What's not to like??????

[Bowdrie]

Originally Posted by CrispyCringle

Looks like its nylon. Slick and fairly soft.

Ah yes, we get to 13 posts before we find out the actual material.
Nylon, while quite strong IS soft/slick and IS harder to effect as good of a seal as PVC, particularly when the fitting has female threads.
Fittings with male threads easily expand the female threads in the nylon.
As the female threaded fitting expands the interface angle changes and doesn't help the seal.
You'll have better results if you just put that manifold together with glued PVC and chuck the threaded parts.
Ok, there is another tack that some may say is "Rube Goldberg", (but it works with nylon).
Use one of the "magic stuff" sealants that others have suggested.
Almost nothing really wants to stick to nylon, I have seen 5200 used, (who would have thought?,) guess what, it works.
Tighten the fittings snugly but not real tight, (an "easy" tight?).
Now, over the ends of the nylon fittings where the threads are you'll place a good hose clamp and tighten it up real good.
The hose clamps that use a "bolt" are better than the "worm gear" style.
If you use 5200, let it kick and then tighten the hose clamps.