runaway charging
 

Good evening all in the Brain Trust. My '31 stock(mostly) truck developed a hole in the radiator, on a hot day. Noticed steam coming out the radiator cap and the overflow tube, towards the ground. The Boyce temperature gauge needle started dropping(no water to measure?) and the ammeter started showing an increase in charge (10 amps) with no lights on. I am using a '57 Ford, 2 brush generator with a voltage regulator hidden up under the gas tank, on the inside of the firewall. This setup has worked well for years. Why did the ammeter charge rate go up significantly with the overheated engine??? Thanks for your ideas!

Re: runaway charging
 

Perhaps the steam/ water from the water flow pipe, which is close to the generator affected the voltage regulator?

Re: runaway charging
 

I think he mentioned the regulator is inside the cab?

Re: runaway charging
 

The voltage regulator is attached inside the firewall.

Re: runaway charging
 

Doesn't sound like the two issues are related. Troubleshoot them independently I'd say.

Re: runaway charging
 

Ditto. It is unusual that two separate issues arise at the same time but these cars can be cantankerous.

Re: runaway charging
 

Probably unrelated but could be that the heat caused some electrical issues, like a increase in resistance in a connection or two or in the generator or regulator. Get out the voltmeter and measure some voltages. I am a fan of a voltmeter in the car in addition to the ammeter. The voltmeter will answer a lot of questions.

Where are you located?

Re: runaway charging
 

Hard to connect overheating to electrical problems. Most likely an odd coincidence. Check your battery for a dead cell.

Re: runaway charging
 

Could also be a failed field relay in the regulator.

Re: runaway charging
 

I had the same problem with my generator in my 59 Corvette. It wasn't water just old age. I rebuilt the generator and solved the problem.

Re: runaway charging
 

* I topped off radiator and ran the truck the next day with normal readings on ammeter and temperature gauge. This engine and A have been very stable for many years, and since things have returned to normal, I can't help but wonder if this was a high heat event. Could the heat cause the contacts, on one of the regulator coils, to stay closed and allow the generator to just keep on charging? Thanks all for the comments!

Re: runaway charging
 

Well you could try heat the regulator with a hair dryer maybe duplicate the issue, Or just go for a drive and enjoy the drive ! ��

Re: runaway charging
 

It could be related. Might pull the regulator and put an eyeball on the field relay and look for anything unusual.