Another Distributor Cap Question

I've got my distributor caps off to install new ignition wires. Does the coil wire just pull out of the caps? The old wires are pretty tight so I thought I'd ask before applying brute force. Both caps look good, no carbon tracks are apparent, though one is the original 26 year-old Marelli, and somewhat grungy, and one is a virtually new replacement.

What's the best treatment of the caps before re-installing? Just wipe 'em out? Emory cloth to clean up the brass contacts? Is it possible to renew the carbon contact? Does everyone use dielectric grease for the wire ends in the distributor?

All of my spark plug extenders (Mayer brand) had holes burned through their insulator by arcing where their rather large inside plug clips almost touch the insulator. The replacements from Kingsborne have much a tidier inside clip with a consistent gap 360 degrees around.

 

To remove the coil wire from the distributor cap slide your fingernail under the brass button and pull up to remove it. You will see the set screw under the brass button. After the set screw is loose the wire will slide out.

I just wiped out the inside of my caps as I had no need to start messing with things.

 

Brass button?

On a QV the coil lead is secured by a spike screwed through it which is behind the centre carbon brush. Grab hold of the centre brush and twist it & pull it gently & it will come out. Then you can get to the screw/spike underneath

 

After further review you are correct it is not technically a "brass button". The correct term was not coming to my head at the time of my post. The bottom line is the carbon brush with the spring to it has to be removed to see the set screw.

 

Thanks for clarifying that. None of the diagrams show that detail. These are the first distributors I've dealt with that employ screws to make the electrical connection with the wire core, let alone hidden screws. I'm learning that Ferraris have many...um...idiosyncrasies.

 

All good, be careful with the spring when you put the brush back in - it can get bent quite easily. The way to do it is to twist it in. Make sure the thing is moving freely as well afterwards - they can stick.

 

Reviving an old thread! My carbon brush was sticking so I had to replace the spring with one I pulled off another brush I got at the hardware store. Is it a good idea to lube the brush and channel it sits in or leave dry? Also how far proud is the brush supposed to sit? It’s meant to maintain constant contact with the center of the rotor, correct? Thanks

 

No lube. Dry. Lube is an insulator. With cap installed, the carbon must touch the rotor.