1969 Olds 98 clock problem...yes it works

[6219_Rules]

It runs fine but when the car has been shut off for more than 10 minutes or so, it stops.

Any ideas why the trickle charge would fail?

[rocketraider]

A lesson in Automobile Clocks 101. These "electric" clocks are actually mechanical clocks that are electrically self-winding. They have a set of points and a small solenoid in them. When the clock runs down, the points close and energise the solenoid. The solenoid then "kicks" the winding mechanism which opens the points and winds the mainspring. This cycle repeats every 2-5 minutes depending on the clock and is the "tonk" you hear from the clock every so often.

The solenoid may be getting weak enough that battery voltage (12v) isn't enough to operate it, while alternator voltage (14v) may be enough to work it while the engine is running. Or the clock may just need a good cleaning and oiling.

You might consider upgrading to a quartz-controlled clock movement. It uses a small quartz crystal to regulate the clock's motor speed at a constant 60 Hz. I have two of those and like them, but I also like to hear the clock tick and "tonk". Plus quartz conversions are expensive- usually about $100. But then NOS clocks are often just as expensive.

Another thing to check is that it is connected to a constant power source. If it is connected to an ignition switch controlled circuit, once the car is shut off it wouldn't be able to wind itself past a couple of cycles. On a 1969 Ninety Eight, the clock power feed is thru the "CLK-LTR-CTSY" fuse thru an orange wire that also feeds the front lighter and glovebox lamp. The lamp feed is a gray wire. Everything grounds thru the main instrument panel ground.

I had a 1976 Custom Cruiser that had had the clock connected to the power trunk wire which is switch controlled. Power trunk option was not available on the CC, but the wire was there in the harness same as the sedans. So sometime in its life, either at the factory or by someone buggering around behind the dash, wires got crossed.

[6219_Rules]

Once again you have answered the question with penache! Thanks! I have had other clocks re-fitted with the quartz movement (most notibly my 47's) so I would not mind doing that again.

I love watching the clock work....when I am not driving, of course! <img src="http://www.aaca.org/ubbthreads/images/graemlins/smile.gif" alt="" />