I am in the process of replacing our Temptrol tub/shower valve with a new one. The old one was leaking through the cold seat and I was unable to remove the seat to rebuild it, despite using the recommended #8 easy-out, vinegar, penetrating oil, heat, -60 freezing spray, 2' breaker bar etc.

On previous rebuilds I have been able to remove the cold seat, but it has been a near thing. They really seem to lock themselves in.

It occurred to me that putting a little never-seize or teflon sealant on the seat threads might make the job easier next time. I called the Symmonds help line, but their advisor said they do not recommend it, but didn't have an good reason why not.

Any suggestions?

Next time use "Seat Wrench". A simple tool, made for seat removal, easy to use. Works every time.

I would definitely follow manufacturer's advice

Milo

A seat wrench and an easy out are not the correct tools for this job. Here, symmons sells specific cold and hot seat removal tools... see images. Without these tools it is highly unlikely that the seats can ever be removed!

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Here are the specific seats (hot is smaller one):

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Mark

Actually, the #8 easy-out is the tool Symmonds recommends using once their factory tool, the one you show in the pictures, has ripped the fragile little broached notches off the cold seat that it is supposed to engage on. Which is a very common event if you live as I do in an where the water is high in minerals or corrosive. I have the Symmond tool, and it was the first thing I tried to remove the seat. When it stripped the notches in the seat I switched to thethe easy-out following Symmond's instructions. Usually it does the job, though not without some trepidation, but occasionally it doesn't. When this happens one has no choice but to buy a new valve assembly. Hence my interest in anything that might make the seats easier to replaceThe "seat wrench" someone else mentions is a universal tool, and, as you point out, will not work on the Temptrol seats.