Water tank shut off replacement - Leaking

[pbyrne]

Does anyone know what the part is and where to get the below?  I can't make out the make on the shut off...

It's leaking, and both are stiffer than I would like.  It takes a fair amount of effort to move it, to the point that I'm concerned that the 'flange' knob bit is going to break off one day.

[waughoo]

Those are just pvc quarter turn ball valves. They are built into a manifold and attached to that mounting board.  I rebuilt mine with off the shelf parts from the hardware store when I got my boat.

[Ron Hill]

pby : Just try Lowes' or Home Depot for a direct replacement!!

A thought

[pbyrne]

Thanks guys!  Do you think I have to replace the whole 'manifold'? The elbow looks glued in..

[Jon W]

With flats on each end of the valve I would think it's threaded together. Only one way to find out.

[Ron Hill]

pby : When you install the new ones I always use "pipe dope" on threaded connections.  Also remember that with plumbing NEVER end by backing up!! always stop/finish by tightening!!

A few thoughts

[pbyrne]

pby : When you install the new ones I always use "pipe dope" on threaded connections.  Also remember that with plumbing NEVER end by backing up!! always stop/finish by tightening!!

A few thoughts

What's pipe dope? And good tip!

[Ron Hill]

bpy " My "Pipe Dope" can reads Pipe Joint Compound W/Teflon - Oatey brand. You'll find it in any store in the plumbing isle.

I always take the part and screw it in counting the turns until that part is oriented to the correct position. Unscrew it back out and add some joint compound to the threads and rescrew it back in counting to the same turns - so you end tightening with the part orientated to the correct position.

A few thoughts

[pbyrne]

bpy " My "Pipe Dope" can reads Pipe Joint Compound W/Teflon. You'll find it in any store in the plumbing isle.

I always take the part and screw it in counting the turns until that part is oriented to the correct position. Unscrew it back out and add some joint compound to the threads and rescrew it back in counting to the same turns - so you end tightening with the part orientated to the correct position.

A few thoughts

Ah! Ok.  That's a very good tip too! I'll do that.

[KWKloeber]

A caution Re tape and Pipe Dope, most do not realize that ptfe tape is NOT recommended for PVC fittings.  It can be used but with great caution.  I've seen schedule 80 fittings that were split - installed by a licensed plumbing contractor.  I even saw a 1/2" air fitting w/ ptfe tape that split an aluminum pump inlet.
For the same reason dope containing ptfe falls into the same category - do NOT over tighten it, or use the plain old stuff.   
Especially on schedule 40 fittings.
Tighten until it splits then back it off 1/4 turn doesn't work.

[Ron Hill]

Ken :  NOT SO The Oatey brand Great White pipe Joint compound w/teflon reads :  "Use on PVC, CPVC, ABS and Polyethylene"

I've NEVER had a problem and even use it on compression fittings!!!

A few thoughts

[waughoo]

One doesn't need pipe dope on compression fittings.  It is unnecessary.

[KWKloeber]

Ken :  NOT SO The Oatey brand Great White pipe Joint compound w/teflon reads :  "Use on PVC, CPVC, ABS and Polyethylene"

I've NEVER had a problem and even use it on compression fittings!!!

Ron, I'll see your 14pt and raise you to 15pt.
Certainly IS SO, mon ami.

Obviously, you are careful when using PTFE.  I too have had no splits -- but that's not true for everyone and so a caution is in order.  BTW, I too sometimes use a lubricant on compression or flare nuts -- typically SuperLube PTFE, because a pipe dope sealant is not needed.

Teflon tape/dope is not recommended for PVC and Lasko says it well:

Don't use Teflon tape, Teflon paste or pipe dope. Do use a sealant.

Teflon tape, Teflon paste and pipe dope is intended for metal pipe and fittings. Metal to metal fitting joints are more difficult to tighten than plastic; the surfaces tend to gall without the aid of such lubricants as Teflon or pipe dope. Plastic fittings do not need this lubrication.

When Teflon tape is wrapped around plastic male threads it adds to the strain and tensile stress. The tendency of most installers is to incorrectly wrap several thickness of tape around the male threads, increasing stain and stress further.

Teflon paste and pipe dope, just like Teflon tape, make threaded joints slippery. Their use on PVC fittings can be an invitation to over-torque.

When working with threaded plastic fittings do use a proper sealant. The right sealant for threaded joints is non-hardening, compatible with plastic and doesn't add slipperiness.   [my emphases added]

https://www.lascofittings.com/threads#:~:text=The%20right%20way%20to%20assemble,Teflon%20paste%20or%20pipe%20dope.

I did not say ptfe CANNOT be used, I said it isn't recommended and that if one does use ptfe DO NOT overtighten. 

The problem w/ plastic fittings occurs because PTFE is NOT a sealant.  It is a LUBRICANT with no sealing property, and PVC is slippery enough by itself so, unlike metal threads, adding additional lubricant is not recommended and can lead to over-torquing plastic fittings.

Reading between the lines, the Oatey site also explains it:

Oatey® Great White® Pipe Joint Compound .... lubricates and seals all threaded joints. ***This compound permits a tighter assembly with lower torque for secure permanent sealing of all threaded connections***. [my emphasis added]

***THAT's the problem -- the DIY-er thinks that the PVC joint is not "tight" because the PTFE makes the joint incredibly more slippery than plain PVC or metal pipe.  So even though the PVC joint may be "made" the natural tendency is to keep tightening (possibly approaching its "breakpoint",) which has the propensity to split the female PVC fitting.  Tapered-thread PVC has a strong tendency to split on the female side when too tight.

Correctly stated, the Oatey site should read:

This compound permits a tighter assembly with lower torque for secure permanent sealing of all threaded connections, therefore when used on plastic threads (PVC, ABS, etc.) a completed proper joint might appear to be too loose, so the user must apply lower torque than on metal threads and not over tighten the connection.

I have witnessed it in medical clinic installations -- after the plumbing contractor completed the job, repeated system pressure and relaxation over time had split PVC fittings that had PTFE.  It can especially happen when a fitting is close to a pump where the velocity pressure shock is the greatest.









 

[Jim Hardesty]

Wow.  A lot of passion over pipe dope and Teflon tape. 
A side note, I use pipe dope on nuts that I want to keep tight but also want to be able to remove easy.  The place that comes to mind is the steering wheel nut, every few seasons I put a dab of dope on it and it stays snub without a big wrench.  I use an oak wrench i put together with some scraps that's about 10 inches long.
Jim

[KWKloeber]

Cool use of that Jim.  I hadn't thought of that use.  Dang, I could have saved money - I bought the large, knurled, hand-tightened wheel nut.

PS I believe there was a can of teflon pipe dope and teflon tape seen near the Titan debris field.  HA

PSS: My fix for the plumber's mistakes that I described was to put a stainless T-bolt hose clamp around and reinforce the repaired fittings.  They were too cheap to use the proper type metal-to-PVC female fitting that has a stainless sheath around it.