1992 Classic Roadsters Wiring question

[Robert T. Faust]

I'm looking for someone who has an older CR (1992) and is using the CR factory wiring harnesses with the Chevette steering column and not the glass type fuse box. After the 4 relays I'm getting some voltage dropping to my lights, balast resistor, winshield wipers,etc. I noticed it when I drove it at night on account of dim headlights and sometimes experiencing starting problems. When testing the voltage going to the headlights it was down to 10.75. All grounds have been tested and are good with clean bare metal contacts at both engine, frame, light fixtures and battery. Also, if battery is low (haven't used the car for awhile) the voltage going to the balast resistor gets dropped even more when starter motor is turning over, and I have to do the old trick of letting go of the key as engine spins for the starter to stop and then the voltage will kick up enough before the engine stops spinning. (Good explanation, HUH?)
Thanks in adavance,
Bob

[dscott]

I'm not sure how to answer this one. To get a voltage drop something has to act like a resistor or the wire is too small for the current draw. I think I would start with the battery and have it checked. A battery can have a memory and only charge up to a certain voltage . I would also check the alternator size. If it is rated below 75 amps that will cause a problem when running several things such as lights, radio, ignition, etc. Usually when the lights dim it is a voltage problem and alternator sizing is important to maintain the proper voltage level. I have a car in the shop now that was experiencing similar problems when the guy runs his big wattage stereo and subwoofer system. We had to add an extra battery with an isolator for the stereo system so we didn't draw down the main battery for the lights, ignition, etc.
Don

[Robert T. Faust]

Hello Don,
You know, the battery is the same one that I put in it when I finished it, about 8 years ago. I never really thought of the possibility of it getting old and dying. Gad zooks, I hope it is something this simple (but I kinda doubt it with my luck).
The reason I was looking for someone with my type wiring and Chevette column is wanting to find out where they found or how they came up with an isolated (12 Volt lead) for the other side of the balast resistor for when starting the car (when starter motor is turning and drawing voltage, I want a 12 volt source not going through the balast but on the side with the coil wire).
Bob

[dscott]

Bob, if you are using an aftermarket ignition system like the MSD you can eliminate the ballast altogether. If you are running the stock Ford ignition box they do develope a problem that you described. Having to back off the key while cranking is usually in the box itself. There is a terminal on the fuse block for a 12 volt ignition source if you wanted to do that. I don't think you need to. Sounds like one of the problems I discussed. Good Luck!
Don

[Robert T. Faust]

Don,
yes I am running an older (Mallory Lit nition) distributor so I need the balast resistor. I think I'll see if I can find that 12 volt ignition source on the fuse block. Per your drawing of the fuse block, what number/slot is it?

[dscott]

It's to the left of the turn signal fuse. I have a fuse block digram in my gallery. It's labled IGN 1.
Don

[slithering]

Bob,

I take it, this is a new problem? Have you checked your voltage on the line side of the voltage regulator? I would have the battery checked, and check to see if your voltage drops more, everytime you introduce a new load to the circuit. Remember, with DC, total amperage is the sum of all points. Higher amperage equals lower voltage.

Chris

[Robert T. Faust]

Many THANKS to both Don and Chris for the information. Looks like I've got a great head start on this quest. First step is to get a new high cranking output battery, then next get the digital meter out and check the voltage at the regulator (Electrical and transmissions are FM to me). Yes it is a newer problem. Can't really complain though as it's been on the road for about 8 years now and has been holding up most excellent. The only thing I've done since the original build was change from the 410 to the 428CJ.
Thanks again
Bob