Alternator Replaced and now problems!!

[Bob H.]

What have I done? I fired up my 66 that has been sitting about a month. I noticed the alternator was getting noisy like a bearing issue although I'v had no problems with it functioning . I thought I would replace it. What have I done. I replaced it with the correct 37 amp, fired it up and all seemed well, that is until it shut off. After it runs for awhile, it will just quit running. Let it sit a minute and it will start and then shut off again. I replaced the regulator and although it appears to charge properly I noticed the resistor is geeting hot and then it shuts off. I guess I should have lived with a noisy bearing. Any help will be appreciated.

[Mark A.]

Re: Alternator Replaced and now problems!!

I'm not sure I understand what you are saying. Is the engine shutting off, or does the alternator quit charging?

[Bob H.]

Re: Alternator Replaced and now problems!!

The alternator is charging and the car just shuts off. I pulled the plug on the alternator and on the regulator and it still shuts off. It will restart over and over but then shut off

[Dave S.]

Re: Alternator Replaced and now problems!!

What have I done? I fired up my 66 that has been sitting about a month. I noticed the alternator was getting noisy like a bearing issue although I'v had no problems with it functioning . I thought I would replace it. What have I done. I replaced it with the correct 37 amp, fired it up and all seemed well, that is until it shut off. After it runs for awhile, it will just quit running. Let it sit a minute and it will start and then shut off again. I replaced the regulator and although it appears to charge properly I noticed the resistor is geeting hot and then it shuts off. I guess I should have lived with a noisy bearing. Any help will be appreciated.

The ignition coil might be the culprit. They quit when they get hot and the car dies. They are hard to test so a donor coil will tell you if that is the problem.

[Albert P.]

Re: Alternator Replaced and now problems!!

When the car dies, leave the key in the "on" position and check for voltage at the coil positive terminal. If there is no voltage there, the problem is probably the ballast resistor opening when heated; if there is voltage there, I'd agree with Dave , and I'd try a donor coil.

[Mark A.]

Re: Alternator Replaced and now problems!!

I think you may have to go back to square one, and find out what is causing the engine to shut off. It may have nothing to do with the alternator. Check power to your coil with the engine running, and make sure you are not dropping power. Check all electrical connections from battery to starter and ignition switch. Also make sure engine is not running out of fuel, due to plugged filter etc. If you systematically check everything, you will find the problem. Good luck. Mark

[Edward M.]

Re: Alternator Replaced and now problems!!

Still got the old alternator? Put it back on. Problem still there? It ain't the alternator?

Is your wiring original? Just moving those old wires around can cause all sorts of problems. They get brittle over the years.