Finally finished restoring my vette and even had the mechanical clock rebuilt and reinstalled, however, it drained the battery overnight.  Guy that did the reinistall says it is shorting to ground somewhere.  I pulled the clock and installed a brand new quartz movement.  It is still slowly draining the battery.  I have 12.56v at the clock lead wire.  I know that this orange power wire is common to the door switches(work) the lighter(works) and the theft alarm (new harness but can't get it to work)  When I turn on the theft alarm at the key switch, I have power down to the new horn and up to the relay and flasher, but no alarm when the doors or hood are opened. When I turn the key swith off I can hear the relay click.  I'm wondering whether the clock and alarm problems may be connected?  Any wire wizards out there that can offer advice?

Disconnect the clock and let it sit and see if the battery still discharges.

The clock shouldn't draw enough on its own to discharge the battery so quickly. There has to be a bad ground or switch left on you don't know about.

Sounds like you're going to be taking fuses out one at a time to isolate the circuit creating the problem. Do a search here on the website...it's been discussed before how to go about it.   

Thanks for the input.  I have disconnected the clock and no battery drain occurs.  It apparently drained the battery quicker with the mechanical movement than with the recently installed quartz movement.  Someone suggested it may be in the clock itself but I can't figure that one out.

If the clock itself is drawing enough voltage to drain the batt. overnite, you should get a fire extinguisher, and put it in the car, or just outside of it. There have been some cars burned to the ground by a malfunctioning clock.
The clock is one of the few things in the car that have 12v all the time. The horn relay, amp gauge(alt), and the headlights are others, as well as the anti-theft alarm. Check your ciggy-butt lighter for pennies/dimes, too!

If the alarm system has 12v at the relay, but it doesn't work, you have a ground problem with the three switches(hood, both doors), or the relay is not getting 12v power feed from the batt. The 12v from the key-switch only energizes the relay, then the pin-switches on the doors/hood make a ground for the system.

The clock will drain the batt over a few days, that's why I have a batt. quick dis-connect on the '74. I would have the clock re-done/repaired, and then check the amp draw on it when it is installed. It shouldn't take that much juice to work the clock...

Thanks for your input.  I should clarify that the shop did not say that the battery was draining overnight, just that when they went to fire it, it was drained.  It could have been sitting for a while. After doing some checking they found the clock to be the culprit and disconnected it.  It had a brand new mechanical works installed in it.  I then put in a brand new quartz movement.  The clock itself works great.  When I installed the quartz conversion, I checked the battery voltage at 12.65 and then checked it over a period of time through the night.  After about 9 or 10 hours, the voltage was down to 12.56 which shows it is drawing, but I don't know if that is an acceptable draw.  I will check into the alarm grounds again, I have checked the door switches once already and we all know how these electical gremlins can hide out on us.  The lighter is new and there is no problem with it, that I know of.  The car just underwent a frame off ground up nut and bolt, but it appears that the shop I hired to do the refit got a little lazy at the end of the project and neglected to pretest some of the electricals.  Let me know what you think about the clock draw.  THanks again for your input.

The clock does not draw power all the time . Only for a split second every 8 seconds or so (not sure could be longer) & the current it draws is so low & fast it would be hard to measure. So somethings wrong with the clock. The inside of the clock is like a windup spring. It energizes winds the spring very fast & until the spring winds down no current should be flowing. So check it on a bench if it draws current constantly something is wrong. The points in the clock could be fused. The clock should never draw a batterty down unless the car has been sitting fo a long trtime.

Thanks, Alan.  I'll check into it.  I have all winter to find the problem.

If it is the clock I know someone up in your area that fixs them & knows more about vets than just about anyone.

Thanks, Alan.  Certainly would be interested in having their name etc.  I guess a lot of people would just leave it unhooked and fugettabodit, but I've already invested time and double money for two different movements and still don't have a clock I can use.  I can and have done most of the resto on my car myself,  but auto electrical is not one of my strong points.

I've had both. The mechanical clock will kill a good  battery in a few weeks.....