Can distributor caps be repaired

[tcslr]

I realize most simply replace. This cap is from a Delco Remy 659B. The cap has a ‘KEM 1482’ embosement. The coil center is worn and I’d like to repair. 
any suggestions? 

[Old buicks 2]

pictures?   what make and year?

[Bloo]

What do you mean "coil center? The carbon brush? Pictures would help.

 

On some caps, the carbon brush is on a spring, and can just be pulled out. On some other cap designs, the brush is crimped in. That would be much tougher but probably not impossible.

[tcslr]

That is exactly right and fair. I will send something this evening. 

Yes, Me Bloo, coil center, carbon brush.

 

Can you tell me why they designed it that way and not used a copper insert?

Just curious. 

[Bloo]

My guess is it wears better? The resistance is insignificant at the voltages used. It is typically spring loaded to make constant contact with the top of the rotor.

 

If it is not spring loaded, then the rotor must take care of that, typically by having a thin metal tongue sticking up to touch a fixed carbon contact in the cap.

 

Once upon a time I believe you could buy those brushes separately. Today the challenge would be finding a cap with a brush of the same outer diameter to steal a brush out of. Generally they just pull out. They are attached to a cone shaped spring that is largest at the bottom of the hole, farthest from the brush. To install, it is a little fiddly to get the big end of the spring started more or less straight, but then you just push.

 

 

[Rusty_OToole]

Dry cell batteries have a carbon rod in the center. One of those might be cut down to fit. Or a carbon starter generator or alternator brush.

[Old buicks 2]

I looked up the distributor number in the big Delco book and found the 659B distributor listing with all the parts.    The cap that tcsir has does not use the spring loaded carbon brush that Bloo is referring to.  Tcsir's carbon is "staked" in the cap with three upsets of the brass insert that surround it.   At one time Delco offered a tool set to change out these carbons and "stake" a new carbon in its place.   Finding one of those tool sets is probably out of the question, and even if you were lucky to find one,  the carbon button required is not available any more.   The carbons that Bloo is referring to were used much earlier by Delco in their distributor caps.   They are not hard to install if you know the technique to use.

 

I have available for sale the NOS cap that Tcsir is referring to.     tsvanmeet@gmail.com    402-359-5762     Tom

[tcslr]

Here is the pictures.  Tom, I'll call you tomorrow.  Many thanks.  Tom

[JV Puleo]

McMaster Carr sells carbon rod. There is also carbon rod used in welding...

I used the McMaster rod in a cap I made.

 

https://www.mcmaster.com/rods/ultra-strength-lightweight-carbon-fiber-rods/

Edited September 9, 2021 by JV Puleo (see edit history)

[oldford]

Sometimes you can find a small tool motor brush that can be made to fit. Electric drills or sewing machine motors would be a good start.

 

Frank

[nearchoclatetown]

McMaster-Carr. Then drill the old one out and glue the new one in. 

[trini]

What is it that is really wrong with the cap? Is it one of the terminal or two off the terminals are burnt out.  It looks to me those terminals are riveted . If it is, drill them out and use silver solder to renew the contacts and rivet them back. The center carbon can be drilled out and replaced. Nimble fingers required. Brush from a starter motor is best suited

[trini]

To loosen pressed" on " objects  boil in water for a few minutes

[Larry Schramm]

A good old time hardware store may have carbon brushes.  Also check a generator/starter rebuilder.

[trini]

Best way to drill a small rivet out is to start with a fine drill. and go thicker until a thin film of the rivet remains.. Then use a sharp pointed object to do the rest. A dremel and a steady hand required

[Peter R.]

[tcslr]

I am going to try to repair my cap.  I plan to take photos and keep detailed notes to share - dont know if it is going to be