Gang, I have a 1968 442 that is draining my battery. My fluke meter is telling me that I have a current draw of 3.012 amps on my battery. I pulled the fuses one by one with no change. Any ideas??

 

Try unhooking the alternator. I assume doors closed and accessories were off?

Pat

 

Yep goes away if I unplug either the alternator or voltage Reg. I had the alternator tested and it was good. Just replaced the VR as well. How can I be sure which is bad?

 

You need to follow the current. Fortunately, 3A is a big enough current flow that it should be hard to miss (about 36W is being dissipated).

You have already tried disconnecting all of the fuses. Now go the opposite route:

Disconnect everything from the horn relay and check for current flow from the battery.

Now connect each single connector, one at a time, each one alone, and see which one causes the drain.

Now check the schematic and see what's on that line, and follow it through, disconnecting everything on it, until you find the source.

- Eric

 

Unplug volt reg plug. Test for voltage at disconected plug at #2 wire. If you have voltage there the alt is bad. The set up is (from left to right) F - field 2 stator R 3 battery 4 ign. With key in off position all reg plug wires except 3 should have no voltage. With key in run position 3 and 4 should have voltage. To repeat with regulator plug unpluged test #2 wire. There should be no voltage. If there is voltage a diode is leaking. The alt may test good for output even if the diode is leaking.

 

I had this issue back in the 90s with my car. It's fairly easy to check diode leakage.

 

Ok, so update: I replaced my voltage regulator and now the 3 amp draw is gone, but the GEN light is on. Only at idle, it goes away at cruise speed. BACK STORY: I replaced the points with PROTRONICS electronic ignition. After reassembling the car, I got the GEN warning light and replaced the voltage reg and alternator.

 

 

Testing the Reg connector, checks out good

 

That is exactly the symptoms of a leaky diode.

 

Looks like the Voltage Reg was bad. It was brand new too, just went poof I guess. The car runs perfect now and no loss or idiot lights. Thanks all!

 

Bad Out Of The Box.

Courtesy of the Great People's Republic and all-around good guys of the Pacific.

- Eric

 

When I went to buy a new voltage regulator, I found two bad ones out of the box. One from advanced, and one from Autozone. One did exactly what yours did, it kept my gen light on. The second one hummed. I know that sounds crazy, but I could hear it hum at low speeds/idle. I ended up buying one from Napa. Only external difference was the napa one was bolted on, where the original was riveted.

 

Notable Bad Out Of The Bow experiences I've had included SEVERAL condensers and two HEI modules.

If there is an ability to test, always test new parts before leaving the auto parts store.

- Eric

 

Bad electrical parts out of the box is not a new issue, I've gotten them since the 70's and not just the chinesium ones. Its frustrating.