Thought I'd throw this out there before I bring the Buick into the shop. I have a 71 Skylark convt. I'm having this issue where the car will start and run, but nothing else has power (Lights, power top, heat/vents, etc.) While this is happening, the GEN light is illuminated. If I hit the gas, it usually makes the light go out, and power will restore to all the accessories. Then occasionally, (say if I hit a bump) the GEN light will come on, and I hear a slight buzzing from what sounds like behind the center air vent. I think the buzz is the same buzz that sounds when the door is open and the key is in the ignition. When the light/buzz combo happens, power again drops from everything, while again, the car is still running. This is usually very brief (1-2 seconds) I'm assuming I have a short somewhere, I just thought I'd throw it out there to see if anyone has experienced anything similar. I thought it may be a bad switch or something? I swapped out with a brand new battery, and the problem still was there, and that's about all the troubleshooting I've done. One side note, the GEN light seems to always be SLIGHTLY illuminated. Been that way since I've owned the car. I replaced the alternator about 5 years ago when I bought the car. Hope I've explained this well enough. Any help or insight would be appreciated. Michael
I find that most of these weird electrical issues are a corroded ground, check the body ground strap.
The buzzing you hear is from one of the relays in the voltage regulator, bolted to the firewall, about midway. You have some loose/corroded connections to look at first. Get it to a shop that has some basic electrical experience. Modern shops don't always have anyone familiar with the older cars.
It may be an issue of a defective ground, or one of a defective connection, both are possible here, so both of the above replies are appropriate. So is the one regarding the unavailability of techs understanding the older cars. The effort, therefore, to learn about what you drive is not only easy, but well worth the effort. First, look at a schematic for your vehicle. They are available at the Zone or Advance. Your goal here is to determine where the problem will affect BOTH of the problems you are encountering. The gen light voltage, for example, will run from the fuse box, to the ignition switch, to the voltage regulator, and to the alternator. The accessories affected by the description come from the fuse box, to the ignition switch, and to the accessories. Common points? The fuse box and the ignition switch both come to mind. The alternator light is controlled by controlling voltage to the bulb. Vo;tage and ground are required for the bulb to operate. If the ignition switch supplies the voltage, which it does when the key is on and the engine is off, and the alternator ultimately supplies the ground. Once the engine starts, the field supplies the voltage to one side of the light, and the key supplies the other, extinguishing the light. If, for some reason, the voltage supplied to the bulb by the key is lost, the voltage supplied by the alternator will re-illuminate the light. The accessories supplied by the key voltage will supply sufficient ground resistance to illuminate the light. Let me know...
I also had a buzzing voltage regulator. It started when I installed a new alternator. The orginal voltage regulators are good up to 55 amps. The new alternator is 60 amps so I switched to an electronic regulator and no more buzzing.
The solid state external regulators good for up to 63A are $12-60 at Rock Auto, depending. Bought a Standard brand one ten years ago for my '67 (though I paid substantially less than today's listed price), still on there and working great. :bglasses:
I too run a solid state unit. Swapped the cover from an original & it looks OEM. Chatter issues with the coils has been a problem. The new style mechanical units are not adjustable as the originals were. Takes a certain amount of voltage to keep the relay closed. Any less & it just keeps trying, make & break....chatter.
Another option is to go 1-wire alternator. Get rid of the ext regulator and double (or better) your electrical plant capacity in one fell swoop. Jamie McClinton has them on here. Mine works great, installation easy, and very affordable. He'll even paint them up any crazy color you want. I went for OEM natural metal look because, well, I'm boring, but if you want Kelly green or fusciaou: , he can do it...:beers2:
It might not hurt to take a good look at the fusible links at the main starter solenoid connection. Those wires can deteriorate and you may be getting an intermittent loss of power right there.
Isn't there another solenoid or relay behind the firewall near the air vent? When I turn my ignition switch to "IGN", there is a relay that clicks somewhere down near the vent system behind the firewall- makes a "bonk" sound- it is not my regulator, because I don't have a regulator anymore. If I don't get the bonk, then nothing works...maybe you have a solenoid/relay that isn't functioning well (due to corrosion?)....?
I vote for the ignition switch (Ray mentioned it, along with a few other things). If the contact that removes power from everything when the key is in "start" ("X" contact, I believe) does not make a good connection when you release the key, it would cause any number of low voltage/no voltage symptoms. That said, I would certainly not argue with the bad ground theory either.
x2 about starting at the IGN switch- there are so many problems to be found there- bad/loose/corroded/melted connections. Agreed. If you want to convert, I believe the later '71 would be the same as my '64, as long as the '71 had an external regulator like my '64. Maybe someone can confirm this? I installed a CS alternator on my '64 Lark. You can buy a CS unit (105 amp), run it 3 wire, and have a GEN light. Do this: Use a CS alternator with 4 pin plug; the plug terminals are marked "SFLP", and wire it like this: S - Run a jumper wire to the + ring terminal on the alt. F - not used L - Connect this to the GEN light. Some people use the old blue wire running to the Delcotron, and splice it into the brown GEN light wire that used to go to the regulator. P- not used. Don't forget to disconnect your regulator. I get way more amperage at idle now- which was the primary reason for going with a CS unit (I've got electric windows, A/C and elec radiator fan).
I think we are getting a little off subject here. The main reason I mentioned the alternator or the ignition switch in this post is due to their commonality to both the alt light and the accessories. Since the alt light requires both battery voltage, and alternator voltage from the alternator field, if one is missing, the result will be a light on with the engine running. Since the original post also included a concern with other accessories, the switch came to mind. Some other things, at this point, include a junction block, either mounted on the firewall or the inner fender, which will affect both the accessories and the alt light. Since, as I recall, hitting a bump had an effect on the issue, I would be looking for loose connections, on the entire current path from the battery, alternator, the junction block, and the connections. Let us know...
I wanted to throw out a huge thanks for all that have responded here. I am going to poke around this weekend and see if I can find anything. I did think about replacing the voltage regulator just to see if that would do anything. Very good chance the one that I have is the original, 39 year old VR...
So here's what it was. Posting this in case anyone else comes across this same problem. Probably would've never figured this out on my own. Took it to my mechanic, and it turns out, my car was missing the small ground wire off the negative terminal that grounds to the body. The large wire that grounds to the engine was there, but not the small ground body wire. (See pic). What's weird, is I've had the car six years, and just started having (major) problems about a month ago. So kudos to everyone who chimed in here to help! And those of you who said "check the ground wire", give yourselves a pat on the back! Thanks again to all - great website. -Michael
I still think something is up with the car. The ground to the fender was not a factory item in '71. Wondering was it put there to cure another issue? Look for a clean solid connection for the NEG cable at the block. Look for a clean solid connection between the RH head & the bottom regulator mtg. bolt. This is done with a bare Cu. braided strap.
The easiest way to check grounds is this, turn on the most accessories you can, with the engine running, and check the voltage between the battery ground, the frame, engine, and body. If ANY voltage exceeds .6 volts, and ground strap between the offending parts is in order. Think about the relationship between voltage, current and resistance. It is Ohm's Law. If the resistance measured is only .2 Ohms, which is lead resistance, and the current is 10 amps, which is typical for any engine running without the A/C, that creates a voltage drop of 2 volts. Any questions?
