2nd cracked bulkhead!

[SmoothSmoke]

Cracked my second 3/4" bulkhead. Both times I used rectorseal 5 sealant. I suspected that I may have tightened too much the first time. The second time I made sure not to overtighten. Could the sealant be the cause? Both times it cracked a day or two after connecting.

[magnoliarichj]

Probably the thread sealant expanding on the inside

[SmoothSmoke]

The sealant is suppose to work with pvc. I hope you're right. This is getting beyond frustrating now.

Teflon tape next time or another sealant?

[clay12340]

I've never had rectorseal crack anything. It looks to me like you've got too much downward force pulling on the bulkhead and it is causing that thin plastic to crack. Is the pipe supported by anything aside from the bulkhead?

[sirreal63]

It is a tapered fitting, you tighten up too much and it splits. Looking at the pic, it appears you tightened a lot more than you needed to.

[LobsterOfJustice]

Did you use tools to get it tighter than hand tight? IME hand tight is all threaded fittings need. Tightening does not ensure a better seal. A few wraps of teflon tape and hand-tight should be fine.

[SmoothSmoke]

Originally Posted by clay12340

I've never had rectorseal crack anything. It looks to me like you've got too much downward force pulling on the bulkhead and it is causing that thin plastic to crack. Is the pipe supported by anything aside from the bulkhead?

Their is only about 3" of flex pvc and a union connected to that bulkhead. I did not connect the entire flex pvc yet.

Originally Posted by sirreal63

It is a tapered fitting, you tighten up too much and it splits. Looking at the pic, it appears you tightened a lot more than you needed to.

Maybe but just not sure. I made sure not to overtighten this time.

Originally Posted by LobsterOfJustice

Did you use tools to get it tighter than hand tight? IME hand tight is all threaded fittings need. Tightening does not ensure a better seal. A few wraps of teflon tape and hand-tight should be fine.

No tools at all. Just hand tightened. I wish I knew the exact cause. I had originally tightened it but it leaked at the thread to elbow. So i applied a bit more rectorseal and tightened to about the same spot as before. Woke up today and it was cracked. It was fine all afternoon yeaterday.

[drew2007]

For that reason alone is why I wouldn't use threaded bulkheads. Try Teflon tape and don't over tighten.

[AcMonster]

Also, spend the extra money on a schedule 80 bulkhead if you can. It is much stronger. make sure it uses the same size hole however, not sure if it requires a larger opening.

[tkeracer619]

Use silicone next time. Don't over tighten it. Make sure to support the plumbing so that it is secure and cannot move.

I too prefer slip instead of threaded on that side.

[SmoothSmoke]

Silicone on the threads? The plumbing is supported. Only 3" of pvc plus half of the union was connected. Surely that couldnt have been the cause.

[tkeracer619]

Yes, silicone sealant on the threads. It won't leak and you won't have to tighten it too much, I promise.

[magnoliarichj]

Light silicone. But I like Teflon. It works great snugs all that stuff up and is reversible.

[SmoothSmoke]

What exact silicone? I mean whats the name of the brand?

[tkeracer619]

Anything aquarium safe. They have small tubes of it at lowes/hd that say aquarium safe on the package.

[SmoothSmoke]

This stuff? If so, I have some on hand from my sump build. Only thing im concerned about is will I be able to remove the bulkhead at a later time.


http://m.homedepot.com/p/DAP-2-8-oz-...0688/100128841

[muttley000]

Originally Posted by sirreal63

It is a tapered fitting, you tighten up too much and it splits. Looking at the pic, it appears you tightened a lot more than you needed to.

This in my opinion. I've never buried a fitting that deep in a bulkhead.

[ca1ore]

Originally Posted by muttley000

This in my opinion. I've never buried a fitting that deep in a bulkhead.

Really! I find bulkhead threads to be 'looser' than standard PVC threaded fittings so I almost always end up threading all the way in. Hand tightening with a modest amount of torque, even with tape, ought not to crack a fitting. Perhaps just bad luck for the OP.

[ca1ore]

Originally Posted by AcMonster

Also, spend the extra money on a schedule 80 bulkhead if you can. It is much stronger. make sure it uses the same size hole however, not sure if it requires a larger opening.

Yeah, that's the trouble. A sch 80 bulkhead requires a larger hole for the same pipe diameter.

[SmoothSmoke]

I counted about 9 total threads on that fitting. I went 5-6 threads in.

Also what is "tight"?? I tightened till resistance. Next time I will leave it looser.

[robertifly]

yep, doesn't matter if dry, greased, sealer or whatever if you turn tapered plastic fittings and even some metal it will split. I like the Teflon paste myself, just use restraint on the tightening, all it really needs is a "good" snug" unless you are trying to suspend something on the horizontal of pipe in which case you're asking for trouble and shouldn't even try that.

[tkeracer619]

Originally Posted by SmoothSmoke

This stuff? If so, I have some on hand from my sump build. Only thing im concerned about is will I be able to remove the bulkhead at a later time.


http://m.homedepot.com/p/DAP-2-8-oz-...0688/100128841

Yes, that will work.

It will easily come apart in the future and you can even reuse the bulkhead if you want.

[nibor75]

Finger tight and then another turn or so.

You should use a non-lubricating (teflon/PTFE free) sealant to avoid over tightening. Something like Loctite No More Leaks or a La-Co Plasto-Joint Stick.

Loads of info in the link below.
http://www.lascofittings.com/threads

[sirreal63]

You may not have over tightened it, it could just be crappy bulkheads.

[nibor75]

You can see the bulkhead is flared.