1951 Buick Special-Lightening issues-NEWBEE

Good day. I just got delivery of my 1951 Buick Special last week. The vehicle is in great shape, however I have some issues with my lighting. When I first got the vehicle off the transport, I noticed the starter would barely turn over, however she fired right up. I drove her around for about 20 minutes and noticed the volt meter jumping from charge to normal and back. That night I noticed that even with the vehicle running the rear running lights turn signals and brake lights were dim to none, and the headlights were also dim. I hooked up a battery charger and left her for almost twenty four hours and it was still pulling 3 amps from the charger. The battery is a very large six volt that appears to be relatively new. The starter spun up a little faster, and the turn signal indicator on the dash blinked a little faster, but the rear lights did not seem to be much better. I drove her around for about twenty minutes, and the volt meter acted the same. When I got back and hooked the charger back up it was pulling 5 amps.

Several Questions- 1. How long should it take to get a full charge on a large six volt battery 6v-6amp charger? It will be almost 48 hours when I get home this evening.
2. Should the lights be this dependent on the battery being fully charged when the vehicle is being driven?
3. Could I be getting an intermittent charge as indicated on the volt meter, and what might explain this?

I know these are probably stupid questions, but please consider that I am a complete novice, embarking on a new learning experience and eager to soak it up.

(trouble uploading photos)

If you do not have one you need to get a volt meter. This will help answer a lot of your questions. With out your engine running measure the voltage across the positive terminal and negative terminals of the battery, it should be around six volts maybe 6.3 volts, Start the engine and with the transmission in neutral have a helper rev the engine up 15 to 1800 RPM (about equivalent to 35MPH driving). Now measure the volts the same way you did before, now it should read somewhere around 7.0 volts (this reading should be steady, not cycling up and down). Next you can use your volt meter to check your tail lights. Remove the red lens and remove a tail light by pushing in a little and twisting (wear a glove so you do not cut your fingers if the bulb breaks). Now turn on the questionable tail lights and use the red probe on your volt meter and touch the center of the light socket, it will probably be a dull silver. Then with the other probe touch the inside wall of the socket (DO NOT LET THE PROBES TOUCH EACH OTHER!). The volt reading should be around six volts engine running and five volts engine off. These volt readings are necessary if you want bright tail lights. This same procedure can be used on the head lights and volt reading are the same.

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Originally Posted by Morgbass

Several Questions- 1. How long should it take to get a full charge on a large six volt battery 6v-6amp charger? It will be almost 48 hours when I get home this evening.
2. Should the lights be this dependent on the battery being fully charged when the vehicle is being driven?
3. Could I be getting an intermittent charge as indicated on the volt meter, and what might explain this?

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1. Assuming a "large" 6V battery to be about 120 amp/hr, 24 hours on your 6A charger should be more than enough to bring it up to full.

2. No, when you are driving the lights should be running on the generator, not the battery. Check the charging voltage like suntree says.

3. Yes, this seems to be a common type of behavior with some of these old generator regulators when the battery is close to being fully charged. I have noticed it on several of my cars when they still had generators, and it didn't cause any problems. These are electro-mechanical devices, and when they cycle they aren't as "smooth" as a modern solid state regulator. The fluctuation shouldn't be cause for worry as long as you are seeing a charging voltage of at least 7 volts.

Ray

Thanks suntreemcanic, raycow, I knew I'd get good responses. The process will start in earnest this evening. Last night after work, I cranked her with ease and drove around for about 45 minutes. The charger had been on for another 24 hours. This morning the starter was sluggish but it started and ran well. I took the long way to work to make sure it got up to running temp. Now as I was trying to run an errand, I get nothing, not even the normal winding up noise. The interesting thing is that the voltmeter showed it charging as I drove to work. Plugged up the charger for about 30 minutes and back she came. Unfortunately I will have to wait to put it on the meter, and I have a buddy that will be a lot of help. Thanks again for the responses.

I've seen MANY times where 12 volts bulbs were replaced for the six volt bulbs. This is the easiest place to start.


Tom T.

Well, I'm back after a long weekend out of the area. As far as my electrical goes, I tested everything under the hood. The battery was reading a solid 6.3 volts while off, and 5.8 while cranking, and 7.8 while running. It appears the battery and the generator are okay. After messing around and eating supper however, I tried to restart the vehicle and got nothing. No lights, no gauges, nothing. We discovered that the quick release on the negative pole was creating some issues so I took it off and attached the ground directly to the battery pole. Since then no more problems. The tail lights and blinker are still a little dim in my view, but they work. I have also noticed that it appears to be starting a little better. Not saying much, but the starter doesn't feel as if it is dragging like it was. I drove her about 30 miles, one-way to do a little shopping, and after my second stop, I noticed the temp gauge almost pegged in the hot. I know there is no auxiliary fan, so I took a chance and drove her to get the air flow, and she cooled down to just above the Normal range. From a layman's perspective, I imagine that big old cast iron block retains a lot of heat, which explains some of the rise in temp, but it didn't feel normal. The coolant level is normal, so the question is, is the increase in temp after stopping normal, and if not, how can it be corrected. I have gotten into the habit of letting her idle for about 30 seconds before shutting it off, not knowing whether or not it is helpful. (boy, I use "normal" a lot)

Yes, the temperature rise after shutting off is normal. As long as it isn't heating up enough to boil and lose any coolant, you don't have anything to worry about. This happens on lots of cars, but it is noticeable only on the ones with mechanical temp gauges.

Ray