Help me figure this out

I refuse to let this little tail light kick my ass but it seems to be doing so.

Single "D" cell battery canister with the little spring thingy in the tail end as it should have. The bulb tested good but It still don't light up when I twist the lens on.

I was told to wrap some electrical tape on the male end of the battery just exposing the contact, but still nothing....UGH!

How does this thing work? any hep would be appreciated.

I think you've got corrosion problems. Clean the end of the spring if you can with a bit of sandpaper, and make sure that the copper bit has clean contact with the outer shell. Sometimes you have to twist the bulb in a bit more to be sure that it's end is making good contact with the positive tip of the battery.

Maybe the corrosion is the problem. I will get at that tomorrow. The bulb is making good contact and screwed in all the way. The copper bit is also snugged tightly into place.

Thank you.

Might try cleaning everything, a vinegar soak of the spring and screw that holds the can to the carrier should do it.
Also try the spring at the top of the battery like on these TL cans:

http://thecabe.com/vbulletin/showthread.php?69728-NOS-Tail-light-unit-Elgin-Colson-Dayton

The negative contacts the mounting screw at the bottom of the can, positive is held away from the bulb by the spring. Screw the lens down and contact is made.
The reason for the tape on the top of the battery is to insulate the spring from the metal part of the battery. If the tape isn't there it won't light.
the only exposed part of positive should be the raised contact.
Big thanks to Jaf/Co Jim for the info.

If the battery is good and the bulb is good, it is all about the contacts.
Chris

Thanks for the info Scott, I'm gonna remove the canister and give it a good cleaning to remove any corrosion. I will also use the tape on the battery.

I'll post the results..

The contact on the end of the bulb should be brighter, it is oxidized. Lightly sand that and I'll bet it works.

Let there be light!

I removed the spring contact in the canister and cleaned everything real well. There was a bit of surface rust and corrosion on the spring but it cleaned up nicely.

I next removed and cleaned the Copper bulb holder. With bulb installed, I placed it against the canister with battery inserted bending ever so slightly to make contact with the canister and battery........ walla! it worked.

I then re-installed the copper bulb holder back into place on the lens and it now works like a charm. I also used electrical tape to wrap the top of the battery exposing only the contact.

I think a combination of everything made it work as it should.

Thanks to those that offered advise and thanks to syclesavage for calling me this morning and recommending that I check the copper bulb holder first. It worked!