Need help ASAP - Rusted ground lug on inside of light niche

[skamp]

I am in the process of replacing a light fixture in my spa (entire light not just the bulb) and the ground lug screw head was rusted off so I am concerned out the ground connection. Here is a picture.

That is the screw head that was incased in the silicon sealant.

Here is the niche showing the wire and bushing.

So is looks like the screw goes through the brass bushing and screws to a boss in the the back of the niche. I tried to twist the bushing but it did not move. I did not want to twist hard and break the niche or the assembly that the screw goes into. Anyone have any experience with these niches? It is a Pentair niche similar to the one mentioned in this PDF.

http://www.pentairpool.com/pdfs/SmallPlasticNicheOM.pdf

Also once I get this resolved I plan on using a stainless steel screw. Also the PDF mentions that the ground wire and lug assembly should be sealed using 3M scotchcast which is a potting compound. I am not sure if my builder used this but did see a bunch of gray epoxy looking debris so could be. Either was it did not total seal it and it is rusted. Any help or suggestions here would be appreciated.

Thanks!

Steve

 

[bent240lv]

Re: Need help ASAP - Rusted ground lug on inside of light ni

They make tools that can remove broken screws/studs etc.they usually attach to a drill and bores the inside of the screw out. If you can't get the screw out see if you can find a grounding clamp that can attach to the lug. Just make sure you get off as much rust as possible so you have a good contact for the ground wire.