Best just to replace the socket.

Light Socket Cleaning Stick found here -- http://www.pbresource.com/tools.html

I recently went through a Chicago Coin Bullseye Baseball and was able to get every socket going again except a couple that I replaced.

Often the issue is that the a socket and its tab are just press fit together. Over time the two pieces have tarnished/corroded so the electrical connection between them is compromised. Cleaning the inside of the socket is important but won't address this issue. Soldering the tab to the outside of the barrel creates a permanent electrical connection between the two and will fix most flickering issues. For details see:
http://www.pinrepair.com/em/index2.htm#connect

/Mark

You can replace the socket.

I've done the other thing. Soldered directly to the side housing of the bulb socket, run a jumper wire to the top of the socket's spring loaded tip for every single socket. Used the 'stick' to clean the internals of the socket.

Still sucks.

Fresh sockets are your answer.

and sometimes the socket is fine but the associated relay switch that controls the light might not be making good contact. Another thing to check if you still get flickering and cleaning or a new socket doesn't work.

Not sure what game this is, but if its a Bally, they made very poor quality sockets. Easiest is to just replace them, or you can do as PinRetail suggested.

There's also the option of replacing them w the new LED strip things that don't require a socket and cost the same.

If you just want to improve the reliability, you can clean as others say, and then you can solder some leads directly to the tip and housing of the socket from underneath... this gets ugly pretty quickly, but it is an option to replacing the socket.

I'll add that this is because the spring tension / corrosion can build up on the common part of the socket, so you are twisting it to get good contact etc.

Also note that as the fiber board material also begins to deteriorate, there is a risk of shorting the lamp as well.

In a Dremel or cordless drill, use a type-443 carbon steel brush on the interior of the barrel. Make certain to get into the side slots for the bayonet as you’re doing it.

443 (resized).jpeg

Then, using a pencil/punch/screwdriver or other rod to fully depress the spring from inside the barrel, use a type-428 brush on the underside of the socket by going all around the protruding pin.

428 (resized).png

When you release the pencil, you’ll see that the now-shiny pin slides into the barrel to make better contact, and the interior of the barrel will make good contact with the bulb.

Similar results could probably be achieved with sandpaper/burnishing sticks. I would expect this to solve 90% of problems but not all. I’ve found this does not work as reliably on pop bumper sockets (bayonet).

You can find these on the shelf at ACE or more affordable knockoffs online.

Edit: if these are backbox-style sockets that have a protruding spring instead of a pin, YMMV. I’ve had good enough results.

In a Dremel or cordless drill, use a type-443 carbon steel brush on the interior of the barrel. Make certain to get into the side slots for the bayonet as you’re doing it.

I did not know Dremel had these. I already ordered a pair. Thanks for the photo and the part number.

This seems to be an article of faith on here, but my experience has been the opposite. I've restored quite a few Bally games, and I've never found the sockets to be any worse than Gottlieb sockets, and in many cases, actually better. I've replaced very few flaky Bally sockets, but lots of Gottliebs, especially those that are on the plates they used for bonus ladders and for score reel illumination. The score reel plates are almost always flaky.

Agree. I've always wondered why people say Bally sockets are worse. They are made different than Gottlieb and Williams sockets and they look somewhat flimsy but I've never found them to be any less reliable.

Now, Bally fuse holders are another story.

Interesting. I've only owned a couple Bally EM's, but never found a poorly performing lamp socket. OTOH, I've had many Gottliebs and rarely have I not had to replace multiple sockets per game as many lamps were dim and flickering.

On the fuse holders, and on Jones plugs, at least the female side, I would agree, although the Jones plugs are ok, people just get a bit rough on them at times.