wet thread protectant

Teflon pipe dope is what I've used on refrigeration service valve caps on the suction side. I haven't had one stick with a thin film of it on the service valve threads. ^_^

TDD

threads tend to rust, and make it impossible to remove the valve cap.

grease. What can be used to keep these threads from rusting?

Dielectric grease? White lithium grease?

Valve cap? Do you mean like on a tire valve? If so, all the valves I have seen are brass. Most cap I have seen in the last 20 years are plastic. Do you have something else in mind?

In case you have steel on steel, or something like that getting wet, I would suggest anti-sieze compound of some type.

Paul

Paul, take a look at the valves in the picture, notice the steel caps on three of the valves. those caps cover the valve stem which is a 1/4" square drive stem which needs a wrench to turn it. Some service valves are made of steel with steel caps which can rust in place. ^_^

TDD

threads tend to rust, and make it impossible to remove the valve cap.

grease. What can be used to keep these threads from rusting?

Dielectric grease? White lithium grease?

Better yet, replace the cap with a non-ferrous one - or a plastic one. Anyiseize works well if you must stick with a ferrous cap.

Better yet, replace the cap with a non-ferrous one - or a plastic one. Anyiseize works well if you must stick with a ferrous cap.

Teflon pipe dope is what I've used on refrigeration service valve caps on the suction side. I haven't had one stick with a thin film of it on the service valve threads. ^_^

TDD

Yes, that, or over the controlling stem. In either case, "should" not be under pressure.

Valve cap? Do you mean like on a tire valve? If so, all the valves I have seen are brass. Most cap I have seen in the last 20 years are plastic. Do you have something else in mind?

In case you have steel on steel, or something like that getting wet, I would suggest anti-sieze compound of some type.

Paul

This is fairly close, the black cap is what rots on.

Paul, take a look at the valves in the picture, notice the steel caps on

three of the valves. those caps cover the valve stem which is a 1/4" square drive stem which needs a wrench to turn it. Some service valves are made of steel with steel caps which can rust in place. ^_^

TDD

That black cap is a Bakelite or fiber filled plastic, not steel and the Teflon paste will work for those too. You can put a dab on your finger and make like a proctologist to the cap making sure all the threads have a light coat of Teflon paste. ^_^

TDD

Just goes to show that I'm bipartisan, open minded, and certainly not racist. I'm using white Teflon paste on black caps, so that they have freedom of motion.

That black cap is a Bakelite or fiber filled plastic, not steel and the Teflon paste will work for those too. You can put a dab on your finger and make like a proctologist to the cap making sure all the threads have

a light coat of Teflon paste. ^_^

TDD

A little dab 'l do ya. ^_^

TDD

A little dab 'l do ya. ^_^

TDD

I've mentioned it before, but I use Teflon tape for similar uses.

It seems to be as good as antiseize but less messy.

I think I even have some on trumpet valve caps. (very fine threads, often left in place for long periods of time, but removal is necessary for lubrication)