? for auto electricians out there.

[casper50]

I got fedup sending my dash clock to a clock repairman in Colorado.  He had it multiple times and it still would not work. Anyway, decided to try and fix it myself. Took it apart and found a wire not connected.  Soldered it back together and tried it.  When I first hooked it up to the battery on the bench I could get current where it was suppose to be verified by my meter.  Nothing would work.  Don't remember why but I changed my leads from light wire to heavy wire and it started working right away. I let it run on the bench for 30 hours.  Worked flawlessly and only gained 1/2 a minute.  Installed it in the car.  Worked for 20 to 30 minutes and stops.  Tap tap on the back and it starts again.  The wires from the clock to the ground and hot connections are small gauge.  Think it would work if I upped the gauge?

[greg g]

My understanding of the workings is that when the circuit is energized the spring gets rewound. Then the clock is powered by the spring till it unwinds enough to make the connection to power again.  So if it winds up the spring, then the clockwork action stops, its a mechanical one in the clock, and not an electrical issue.  Like anything six volt it should benefit from low resistance through wire connections and to ground. There might also be some contacts that need cleaning or adjusting to assure the connection is properly made when the spring gets to its wind me up again position.

[casper50]

When I have it on small gauge wire leads the points close and nothing happens.  When I switch the leads to heavy wire it will immediately wind the clock and will keep doing so for hours.  I have cleaned the points.

 

Edited August 16, 2018 by casper50

[Andydodge]

Casper..........when I found out how expensive 41 Plymouth clocks were, a NOS one was listed on ebay at over $700 I took a real clean scan of it from the net, resized it to suit the hole in the dash and stuck the pic behind a piece of perspex.....I then had a clock that was 100% accurate at least twice daily.............although its accuracy was debatable for the rest of the time, but it looked good...........sorry.......I'll go back in my corner now.......lol........andyd 

[casper50]

I have two.  Took the best pieces of both and made one.  It works perfect on the bench with heavy leads from battery to clock.  When I use smaller gauge wires nothing.

 

[greg g]

Then give it the big wires and let he rip!  

[DrDoctor]

Andy,

   I did basically the same thing on our ’46 Plymouth Special DeLuxe Club Coupe. and like yours, the clock keeps excellent time—once in the morning, and once again at night. Warmest regards to you!!!

[casper50]

Replaced wires with larger gauge.  Works fine for 24 hours on the bench.  within 90 minutes mounted in the car it stops.

Edited August 18, 2018 by casper50

[greg g]

Wonder if something in the mount is causing a bind in the clock work?  Try setting it in place loose and see what happens.

[casper50]

will do.

 

[P15-D24]

Instrument Services in IL, will convert to update internals. 

[DonaldSmith]

One difference between bench-testing and in-car performance of the clock would be the ground circuit.  Clock case to dashboard, dashboard to body, body to engine, where the ground cable is attached.

There might be just enough resistance in the ground path to compromise the winding mechanism of the clock.  That's one heavy-duty thunk every few minutes. 

[casper50]

the clock has it's own ground wire. tested both hot and ground connect points with my meter everything reads good.

[DonaldSmith]

One can never have too many ground paths. 

[Lloyd]

Dont know a thing about this type of clock except what Greg just added. But it sounds like it needs a lot of amps to work. I would think the heavy gauge wire would afford that opportunity. While its in your car might try and run some of that heavy gauge wire straight from the battery to the clock. One wire at a time, which ever one works the clock then the other one you are using would be at fault.

 

[casper50]

good idea Lloyd.  Might run the hot straight from the battery.

[greg g]

Put an inline fuse in the power feed.  I would start with 15 amps.

[DonaldSmith]

The clock shouldn't need so much amperage.  Someone in another thread mentioned a 2-amp or 3-amp fuse?  At the back of the clock is the winding mechanism with coil.  There are numerous pivot points that may need lubrication.  Or maybe the clock is just wearng out.   (This coil needed re-soldering its connection to the point system. The coil moves the winding arm, which powers the clock mechanism.  As the arm reaches the end of its travel, usually taking a few minutes, the points close, moving the arm again.)    

 

Edited August 18, 2018 by DonaldSmith
typos

[casper50]

yep that's the way mine works.  Mine has been sent out twice for cleaning and repair.  they didn't repair it obviously but hopefully they oiled it.  Like I said it works on the bench for over 24 hours straight.  I put it back in the car this afternoon and nothing.  Guess it's going to be correct 2 times a day and I'll have to live with it.

[NickPickToo]

On 8/18/2018 at 12:35 PM, DonaldSmith said:

One can never have too many ground paths. 

My mom grounded me again just a few days ago.  Spent more time last weekend taking the front end off the 47 than studying for the summer reading test

[casper50]

Sorry bout that.  Have to balance stuff Nick.

[NickPickToo]

On 8/18/2018 at 10:49 PM, casper50 said:

yep that's the way mine works.  Mine has been sent out twice for cleaning and repair.  they didn't repair it obviously but hopefully they oiled it.  Like I said it works on the bench for over 24 hours straight.  I put it back in the car this afternoon and nothing.  Guess it's going to be correct 2 times a day and I'll have to live with it.

Maybe this gets me kicked out of the forum for being too young and breaking some sort of sacred restoration code but why not keep the face and arms modified to fit newer clock guts behind it.   Then change the battery once in a while?

[casper50]

That's what a lot of folks do.  I'm kind of anal and if I own it I want it to work correctly.

 

[NickPickToo]

2 minutes ago, casper50 said:

That's what a lot of folks do.  I'm kind of anal and if I own it I want it to work correctly.

 

Kind of understand.  Amazing how older tech worked.  Guts of the clock are even beautiful.

[casper50]

I have always been amazed that anyone back in the 1700's could figure out what gears they needed let alone hand make them.