Stuck screw in shower valve handle

MarkB_MI · Nov 26, 2016

I had to remove the handle from a shower valve yesterday. Although I was able to get the set screw backed out enough to pull the handle, the screw became stuck and wouldn't move in either direction. A replacement handle is 25 bucks, so I decided to see if I could salvage the old handle.

First off I filled the handle with Kroil and let it sit for an hour. No difference.

I'd never tried applying heat to pot metal before, but I figured worst case I'd have a pool of molten zinc on my workbench. I put my smallest brazing tip on my oxyacetylene torch, placed the lever in the vise using padded jaws, and started heating the lever hub. After a couple of minutes of carefully heating the hub and trying to turn the screw it came free. The stainless screw was still in good shape so I just dipped it in grease and put it back in. The lever looks good as new and the chrome plating doesn't appear to be damaged at all. I'm sure I'll use this technique again in the future.

Jeff NWOH · Nov 26, 2016

It's amazing what the old flame wrench will do. I'm not one to soak stuff for days or weeks. When I want it apart, I want it done now. Very rarely does the torch let me down.

wsmm · Nov 26, 2016

My problem, is a lot of stuck bolts and nuts are in the rear of my vehicles near the gas tank. Don't feel safe even thinkking about using a flame wrench there!

ditchwitch · Nov 26, 2016

JD Seller · Nov 26, 2016

I have found that using a small propane torch works well on these type of fixtures. The heat is not near as hot.

MarkB_MI · Nov 26, 2016

>I have found that using a small propane torch works well on these type of fixtures. The heat is not near as hot.

I didn't have my propane torch handy, but even if I did I probably would have used the acetylene torch anyway. My main complaint about propane torches is they're not very well focused. When I put a small brazing tip on my acetylene torch, I can apply a lot of heat very quickly to a small spot. In this case, I was able to get the screw loose without getting most of the lever very hot.

johnlobb · Nov 26, 2016

Kroil or Silikroil does work, but 1 hour is probably not enought time. Overnight is much better, I have been amazed what Kroil can do...

K Effective · Nov 26, 2016

Well, I've drilled out three of those pot metal Kohler handles with stainless set screws here at our place- I can't figure out how you got the torch in the shower without melting the whole thing onto a big ball...

Replacement handles were purchased online for about $8 ea, set screw lathered in nev-r-seize this time, I tell you what!

Frank 41 · Nov 26, 2016

I broke two self taping 5/16 screws in my aluminum drop deck. I broke them with a rachet. Should have used the impact with low air pressure. I had to remove the center nailer to do some wiring for a dump valve. One was broken flush and the other was above the bottom about 3/4 inch. I welded a nut on , let it cool and popped it right off again. I did that twice. I heated the other one with the torch, let it cool and tried the vice grips. Neither one budged. The old steel trailer did not do that. Just plain old rust. Since I never plan on using it, I probably omit them or drill another one close by. Even the small bolts holding the license plates were corroded. All the new bolts that I replace are stainless now.

Royse · Nov 26, 2016

"I can apply a lot of heat very quickly to a small spot."

Absolutely the way to go.
Don't heat everything around it for a long period of time.
Precision heat, applied quickly, then get out.
I did micro-miniature soldering under a microscope on multi-
layer circuit boards for years. Anything else destroyed them.

MarkB_MI · Nov 27, 2016

> I can't figure out how you got the torch in the shower without melting the whole thing onto a big ball...

The handle was in my workshop (about 15 miles from the rent house shower) when I took the torch to it. I managed to loosen the screw enough to pull the handle off the valve, but at that point the screw was frozen solid.

MarkB_MI · Nov 27, 2016

> I broke two self taping 5/16 screws in my aluminum drop deck.

I've had good results removing steel fasteners from aluminum by applying heat directly to the fastener. If it's a small fastener, I'll use a brazing tip on the acetylene torch. Heat the fastener cherry red and turn it out hot. If it starts to grab, apply more heat and keep turning. Obviously the fastener can handle a lot more heat than the aluminum it's threaded into, so it's important to focus the heat on the fastener. I think your mistake was allowing the fasteners to cool before you tried to remove them.

Yes, stainless steel fasteners with anti-seize are a must in aluminum. If you can find 316 stainless fasteners, they're even better than the commonly-available 304 (18-8) stainless.

Stuck screw in shower valve handle

MarkB_MI

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Jeff NWOH

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wsmm

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ditchwitch

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JD Seller

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MarkB_MI

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johnlobb

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K Effective

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Frank 41

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Royse

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MarkB_MI

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MarkB_MI

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