clock repair

[GoMangoBoys]

Our clock from the 70 Challenger w/ Rallye dash is not working.  When we connect it to 12V, the second hand sweeps about a quarter rev and stops.  If I disconnect the power and reconnect it, sometimes it starts up again and runs a little way before stopping again.  I think either something is overheating or some sand is in it.  The previous owner sandblasted the car with the dash in it still.  There is sand in everything.  I was hoping to take it apart and clean it all out, but the face is attached with some small rivets that I will not be able to replace.  Looks like the face has to come off to do anything.
I am planning to just buy another one at Carlisle this weekend unless someone tells me an awesome and easy solution to repairing this one.
Thanks

[DeathProofCuda]

There are kits you can buy to replace the original guts with updated quartz internals.  The downside is that your second hand will no longer "tic", it just does a continuous 60 second sweep around the dial.  I don't really remember the process, but I rebuilt mine years ago on the kitchen table with very minimal tools, so it obviously wasn't very hard.

Here is what I used:

https://www.clocksandgauges.com/quartz-conversion-kit.html

Apparently I used kit # R-3035 (still have the box).  Looks like you can pick them up on ebay now for $87.

[Jay Bee]

What DeathProofCuda said. I converted 3 clocks using that kit.

[GoMangoBoys]

Does the kit include suitable replacement fasteners for the rivets that hold the face on?

[DeathProofCuda]

Yes, according to the instruction sheet, the "R" kits contain 3 or 4 aluminum rivets and there are instructions on how to remove the original rivets and install the new ones.  You just use a small hammer to peen over the back side of the rivet.

[Joegrapes]

I had the same problem with my clock. When you look at the workings you'll see what looks like a set of ignition contact points. When the clock spring winds down the points touch making electrical contact and a solenoid winds the spring back up. It does this over and over again. Eventually the contact points get corroded and stops making an electrical connection. I've cleaned the points with some Emory paper and the clocks works good for awhile until it happens again. I got tired of doing this so I just replaced the clock with a modern movement. The only difference is the original second hand ticks and the modern one moves in a constant motion. But at least it's been working for about 10 years now.

[Skdmark]

I found this article on how to diagnose and repair a mechanical clock. The example was from a Buick, but the author said they are all basically the same from that period. I have 2 cars with broken clocks and would like to keep the "clunky" tic-tock.

https://www.oldcarsweekly.com/restoration/putting-the-ticktock-back-in-your-old-car-clock

[RUNCHARGER]

About 30 years ago I found a place to repair my Challenger clock. I was amazed that they said it would be $50 without even seeing it. About a decade later I found out about the points......

[Jay Bee]

I used to clean the points/contacts too before finally doing the kit conversions. I found that the clock can be opened up just so many times before the tabs break off.

[DeathProofCuda]

Just remembered this morning that I had actually purchased my Instrument Specialties, Inc. clock kit through Real Time Engineering.  These are the same guys that build the solid-state instrument voltage regulators and replacement circuit boards for Mopar tachometers. 

https://www.rt-eng.com/

It looks like they no longer sell the clock rebuild kits, but back when they did they provided a much better set of directions, with pictures included, that is specific to the Mopar E-body clocks.  I've attached a pdf copy.

[Mopar5]

Our clock from the 70 Challenger w/ Rallye dash is not working.  When we connect it to 12V, the second hand sweeps about a quarter rev and stops.  If I disconnect the power and reconnect it, sometimes it starts up again and runs a little way before stopping again.  I think either something is overheating or some sand is in it.  The previous owner sandblasted the car with the dash in it still.  There is sand in everything.  I was hoping to take it apart and clean it all out, but the face is attached with some small rivets that I will not be able to replace.  Looks like the face has to come off to do anything.
I am planning to just buy another one at Carlisle this weekend unless someone tells me an awesome and easy solution to repairing this one.
Thanks

The face of the clock does not have to be removed to repair the existing clock. The housing seperates by pulling back the 4 bendable metal tabs on the housing with a pick, My clock would nor budge  and works fine after spraying out mechanism with contact cleaner.

[Mopar5]

Here are the 4 tabs

[dylo]

Mine had a broken main spring and also dirty points. After fixing these and figuring out how to re-calibrate it, its as good as new...

...until one of the other 400 moving parts break.