Clock work

[Alshere59]

Well the mail man brought me a clock for my car today. It was pretty cheap so I thought why not look at it, at most I would end up mounting a different movement.

So after a few searches on google and here, I took it apart to see if it would work or at least get an idea what would fit. After seeing a few discussions but none with pictures I thought why not post what I found. So for the new members like me, here is what little I know.

The first two pics just show the basic insides.

Basically it works off the idea, that when it winds down the points close and an electric magnet energizes and pulls the arm back. This winds the clock and opens the points. So a repeating cycle. If you look at the last two pictures you can see the points are open then closed. You can also see the end of the electric magnet below them has a piece of metal that is higher in pic three than 4. That is the arm that the magnet pulls and winds the clock.

After looking it over I found mine had the points welded/stuck closed.

The way I understand it, when you run the battery down to the point that the magnet doesn't work but the points have enough current flowing through them to cause them to stick.

On mine it also loosened a solder joint to the magnet also. Probably when they charged the battery it melted the solder joint because the points were stuck and then it had more than enough current.

To be honest if you can read a meter you have enough skill to trouble shoot this. It is very basic.

I just thought of posting this after I put it back together so no pics of it disassembled.

So after getting my electric magnet winding mechanism working it ran for probably 4 minutes then stopped before the points closed. So with a bit more research I found that contact cleaner works to clean the clock mechanism. So since I had some radio shack lubricated contact cleaner I sprayed down the inside, making sure not to get it on the dial. That did it. Now it works as advertised.

Things I would do different.

Initially I would take it out of its case before I tried it. This would let me check the points and manually pull the winding arm up to see if it would at least run. How do I know if my first try didn't melt the solder?

Probably cleaning it in an ultra sonic bath. I can get done for free. Just didn't think of it at the time. At minimum use a non lubricated contact cleaner. Just seems like with everything lubed it will attract dirt and dust. Many web sites show where and how little oil to use. Since its working now, I will probably do the bath if it stops again.

Anyway hope this helps someone. For what I have invested and no risk that I can see it seems like a worth while check.

Normal disclaimer: Try it at your own risk.

Hope this helps someone.

Al

[BobT-47P15]

Al, I think you have the repair thing down pretty good.

My son in law took his P15 clock to a jeweler friend who went thru

it. Found a couple problems like you described. Once he worked

on it - it now is running. I think you are right....don't want the

lube to be too oily or it will attract dust. Glad you made progress.