Cleaning regulator and cutout contacts

[Member 10617]

This topic has been mentioned today (by Randall) in another thread, but I thought it might be helpful to focus a bit on it.

Moss states: "Cleaning the Contacts. Start with the regulator contacts. Fold a piece of fine grit sandpaper and drag it through the contacts once. Clean the contacts and surrounding area with a rag and some rubbing alcohol. Use sandpaper with non conductive grit.

"Next, clean the cutout contacts. Fold a piece of fine grit sandpaper and drag it through the contacts once. Clean the contacts and surrounding areas with a rag and some rubbing alcohol."

However...

A manual on Generator Output Contol states: "Oxidation of the points. It is important to note that the regulator points are made of tungsten, and should be cleaned with carburundum stone or silicon carbide paper, but the cut-out points are made of silver and should only be cleaned with fine glass paper. All dust should be removed, preferably with a cloth soaked in methylated spirit."

On recent threads, respondants have said they use a burnishing tool or card stock to clean these contacts, although Randall repeats the warning about cleaning the cutout points.

Is card stock OK to use on both of these contacts? Or... Is there some other safe and commonly available substance to use in place of carborundum stone, silicon carbide paper, or glass paper (whatever that is).

 

[Geo Hahn]

I cringe when I read 'sandpaper' in that instruction -- not something I would ever want around electrical parts.

I'll leave to the more experienced for a definitve answer but a bit of card stock and some Radio Shack Contact Cleaner worked for me.

 

[CJD]

I cringe when I read 'sandpaper' in that instruction -- not something I would ever want around electrical parts.

As long as you have used the paper on something greasy first it'll work awite...keeps it slick to pass on through.

(and yes, I am joking...lest anyone gets an idea to try it)

 

[Sarastro]

Regardless of what the contact points are made of, you really don't want to use any kind of sandpaper. The problem is that there's always some amount of grit left embedded in the contacts, and that prevents good electrical contact. The result is sparking, which burns and erodes the contacts, putting you back where you started.

One good thing for cleaning switch or relay contacts is an ordinary pencil eraser. But you won't be able to get it to the regulator relays' contacts without disassembling them. Best to use paper, cardboard, or a burnishing tool. The latter will probably be more effective; the former is OK if the problem is just that they need a little cleaning up.

 

[Member 10617]

So.... I used a piece of paper and slid it gently between the contact points...

Wrong move!

For some reason that action opened the contact points and left them open (no, I didn't do anything to the lock nut or screw) and the car wouldn't start. Fortunately I had a back up regulator, installed it, and the car was back on the road.

Lesson I learned... leave the regulator alone or leave it to an "expert."

And why did I try to clean the points? I was having some kind of electrical problem and was going down the list of possible solutions. Turns out the problem was with my battery. It registered 12 volts, but went "bad" when a load was put on it. Battery was only 2 years old... but still under warranty, so I got a "free" new one.