Tips for removing old pool light screw that is stuck tight?

[aztodd]

Hi - I have an old pool light original to the pool that burned out years ago now. I recently had the pool drained and thought I might go ahead and replace the bulb, but the top screw holding it in place was NOT going to budge. It was unscrewed maybe 1/4th of an inch already for some reason, so I tried using a small vise-grip to get more leverage... well I could feel the screw starting to shear, not turn, so I stopped and let it be.

Does anyone have any tips or solutions that might work here??

Not sure the make/model but this picture looks practically identical to what I have installed.

 

[Bperry]

Try spraying some liquid wrench down the hole and tighten the screw a little bit, then loosen, back and forth to try and get the solvent to break through the rust.
If it eventually breaks, you can remove the trim ring and use an easy-out to hopefully remove it.

 

[aztodd]

Try spraying some liquid wrench down the hole and tighten the screw a little bit, then loosen, back and forth to try and get the solvent to break through the rust.
If it eventually breaks, you can remove the trim ring and use an easy-out to hopefully remove it.

Thanks - I'll have to try that the next time I drain my pool low enough.

 

[peterrietmann]

Just went through exactly the same with two Pentair lights, one in the spa which i could empty , the other in the pool. Both screws would not loosen, eventually Phillips head was stripped so used a screw extractor bit that eventually took the head off the screw. In the spa i could use impact driver , in the pool i spend a good hour with a hammer, a punch, and the extractor bit with a creasent spanner. Anyway was able to get both lights out at this stage.

Using large grippers on the remaining protruding screw shank, was useless, the screw would not budge it at all, eventually the screw sheared off and i used a regular drill bit to drill it out. The screw seemed to have melted into the holding bracket. I ended up getting a 10-24 SS nut and using pool epoxy fixed it into position so a new screw would catch on it and lock tight in place.

The other fixture that is under water, i left the exposed shank and have ordered a pool light wedge to fix it back securely.

I have one light to go and imagine that the screw is also screwed. I would guess the lights have been in the pool for at least 10 years. Probably a good idea to loosen and tighten the screw every season. to avoid the rust build up, but who knew