12V lightbulbs throwing sparks

[photomikey2]

'61 International Overlander. Each light fixture in the whole trailer has a 120VAC bulb/socket on one side and a 12VDC bulb on the other. The AC bulbs all work fine. The DC sockets have not been used in... 20 years or so. I have 12VDC bulbs (tested, work fine). When I put one in a socket, they won't illuminate. I can wiggle it around a little and it'll throw sparks out of the socket. Same deal out of every socket in the trailer - none of them work but if you jiggle it it'll throw sparks. I assume there is some corrosion in the contacts. Can I replace the sockets? Dielectric grease?

[uncle_bob]

Hi

I'm guessing you already checked to make sure the 12V and 120V power isn't all crossed up. If not, that would be the first thing to check.

I'm not quite clear on just where the sparks are flying out of. I'm assuming they are coming out between the bulb and socket. That sounds a lot like the base size on the 12V bulbs isn't correct for the sockets. Normally with a screw in light fixture the bulb should be very secure when screwed in. If it's a pin base then wear out is pretty common. (not clear which it is from the picture)

Normal "repair" for a light socket that's past its use by date is to simply replace it. There isn't a lot of rebuilding you can do. Cost wise. .... they should be dirt cheap.

Bob