Anything that can fry a voltage regulator?

Zymurgy

Old Man with a Hat
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I have time waiting for a tow. My system wasn't charging and I have a dead battery 30 miles from home. Last fall it did same thing, I had a brand new electronic voltage regulator on the shelf installed, no other problems until now.

I haven't diagnosed that it is the regulator but can a bad alternator fry a regulator? If it is bad it would be my 3 in a year and a half.

At least the morning sun is pretty on the dash.

20180623_092253.jpg

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I cannot answer your question, but at least you've got a nice morning to enjoy. It's been raining here.
I got lucky it started to sprinkle when the tow truck arrived, can't put the power top up with a dead battery.
 
Time to start carrying a cheap jump box in the trunk.

I never thought I'd say this, but given the failure rate of the earlier style electronic regulators, maybe it's time to consider going to the '70 style isolated field alternator. That would give you a more dependable regulator.
 
Check the ground for the regulator, they need to have a good ground to operate. The main thing that will "cook" an electronic regulator is unhooking a battery cable with the engine running, will usually fry them every time. Look at the back of your regulator for a burned spot. Also the quality of many after market regulators is highly suspect. Unless you are running electronic ignition, you might have better luck with a mechanical regulator.

Dave
 
As you may know, I sell the electronic solid state voltage regulators (on eBay & to folks who contact me directly) that are made by Regitar, a worldwide manufacturer of voltage regulators, alternator rebuilding components and all kinds of electrical components for the automotive industry.

The ones that I sell have an extremely low failure rate and usually don't work correctly when first installed if they are bad. A bad or lost ground can be an issue as can a number of problems that cause a significant spike in the current to the voltage or amps going to the voltage regulator and a defective battery can also cause them to fail. Suggest doing a full analysis of the alternator and battery.

The quality of parts store rebuilt alternators is pitiful these days. They only replace the failed component and do not rebuild the entire alternator. Have a reputable alternator rebuild shop rebuild one of your alternators and it will likely last as long as you have the car. Just my 2 cents based on my experience.
 
As you may know, I sell the electronic solid state voltage regulators (on eBay & to folks who contact me directly) that are made by Regitar, a worldwide manufacturer of voltage regulators, alternator rebuilding components and all kinds of electrical components for the automotive industry.

The ones that I sell have an extremely low failure rate and usually don't work correctly when first installed if they are bad. A bad or lost ground can be an issue as can a number of problems that cause a significant spike in the current to the voltage or amps going to the voltage regulator and a defective battery can also cause them to fail. Suggest doing a full analysis of the alternator and battery.

The quality of parts store rebuilt alternators is pitiful these days. They only replace the failed component and do not rebuild the entire alternator. Have a reputable alternator rebuild shop rebuild one of your alternators and it will likely last as long as you have the car. Just my 2 cents based on my experience.

I was just wondering if I still had my original alternator and have it rebuilt if it is my alternator. If it is my regulator please post you Ebay link .

Thanks everyone for the feedback.
 
If everything had been working well, battery charging and all, then "dead", it could well be a bad diode in the alternator. As they are "one-way switches", easy to test. Easy to replace.

Look for "reman" alternators rather than "rebuilt".

Nice instrument panel paint and chrome!

CBODY67
 
The main thing that will "cook" an electronic regulator is unhooking a battery cable with the engine running, will usually fry them every time.

Dave

This statement just hit me while I was mowing the lawn. I might have cause the failure in all three. My positive side of my battery is not tight, I went over some railroad track today which were really rough, if it arched could that be enough?

The stupid part is I never unhook my battery except at winter time, the terminals are very clean and it always starts. I know it will always be tight now.
 
This statement just hit me while I was mowing the lawn. I might have cause the failure in all three. My positive side of my battery is not tight, I went over some railroad track today which were really rough, if it arched could that be enough?

The stupid part is I never unhook my battery except at winter time, the terminals are very clean and it always starts. I know it will always be tight now.

The sudden surge from the connection being loose is all it takes. The old style mechanical ones were not bothered by that, despite all their other limitations.

Dave
 
Dave I believe you just saved me a lot of future grief thanks so much.

Another issue was .my failing condensers, could a loose battery terminal fry them too?
 
Michael, I will ship the Voltage Regulator out on Monday. Will get you tracking info etc. tomorrow.

I will be bringing some with me to Carlisle.
 
Dave I believe you just saved me a lot of future grief thanks so much.

Another issue was .my failing condensers, could a loose battery terminal fry them too?

A condenser is designed to operate in an electrical system that involves sudden surges of power, so no. Most likely a voltage problem to the distributor (too high from an improperly wired ballast resistor) or poor quality condensers.

Dave
 
The regulator grounds to the firewall through the mounting bolts, but I still add a ground wire just to be safe.
 
The regulator grounds to the firewall through the mounting bolts, but I still add a ground wire just to be safe.

Great idea, I resprayed the firewall during the restoration, this could be part of the problem too. I like the idea of adding a ground wire to be sure, thanks.
 
Thanks for the great advice everyone I am feeling much better that these tips will solve my problem, plus if I have an extra regulator in the trunk it will never go bad again right. :)
 
Great idea, I resprayed the firewall during the restoration, this could be part of the problem too. I like the idea of adding a ground wire to be sure, thanks.

Fresh or thick paint can be an issue with getting a good ground from the voltage regulator mounting bolts as the bolts don't always get a good ground.
 
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