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| | | Forums66 Topics128,136 Posts1,056,425 Members48,441 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Oct 2009 Posts: 83 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2009 Posts: 83 | I warmed up the 57 today, I wanted to get rid of what ever was in the crank case. So I got her running steady, good and warm. Shut it off, I noticed a waxy kind of smell, I figure it was the motor oil, I rested my arm on the voltage regulator when draining the filter canister and it was more than warm and I looked over past the engine and noticed smoke rising above where the generator is located. I got distracted and never did go over the other side of the truck to check the generator; any thoughts on what is going on?
1999 GMC Yukon 1957 GMC 100 Panel
| | | | | Joined: Feb 2009 Posts: 49 New Guy | | New Guy Joined: Feb 2009 Posts: 49 | Regulator might have fried, for lack of better words, letting the generator put too much current through it. Could you see when it was running if there was any arcing/smells FROM the generator going on? | | | | | Joined: Oct 2009 Posts: 83 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2009 Posts: 83 | Saw no smoke while the engine fan was blowing air all over, didn't noticed the smoke after the engine was off. There is nothing else over there that would smoke so while I didn't see the source of the smoke directly I am pretty sure it was the generator. I didn't hear any arcing but then my truck needs a new exhaust system as the one on it is pretty rusted and loud. I think I need to ck the generator output and if that is ok I need a new regulator. I put one on my 65 sub years ago, it was solid state; I don't remember if I had to polarize it on not but I don't think so.
1999 GMC Yukon 1957 GMC 100 Panel
| | | | | Joined: Dec 2006 Posts: 720 'Bolter | | 'Bolter Joined: Dec 2006 Posts: 720 | I had an isse where my gen light was staying on when I shut off the truck. A relay in the regulator was stuck closed and allowed the battery to fry my jenny. ALL of the solder in the armature was gone & spattered all over the interior of the housing. Fun times,... And since I'm too cheap to buy an alternator that keeps my stock look, I keep an extra reg and jenny in my shop. 1956 GMC 370 dump " 'Tater "1970 VW Volksrod "the Black Bomber" 2007 Chevy Avalanche 2020 Jeep Cherokee Trailhawk, 2005 Harley Davidson FLHTCUI I dig all cars, old and new, whether they were hammered out of American iron, German steel, or Japanese tin cans. Being unable to appreciate them all is missing out on a world of great things. But thats just MY opinion! :P
| | | | | Joined: Nov 2007 Posts: 190 Shop Shark | | Shop Shark Joined: Nov 2007 Posts: 190 | sounds like the regulator stuck and let the generator charge at full capacity, this will burn one up fast. The smell and smoke was probably from the armature insulation. If you look in the rear of the generator and can see solder slung around then you know its bad. Ken | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | In the late 60s, I bought a cheap voltage regulator from JC Whitney for a 1948 Chevrolet Panel Truck. After 200 miles (on a 400 mile trip), the lights got real bright for a short while. Then, we smelled an odd odor from the engine compartment, and the ammeter registered zero.
A quick inspection of the engine compartment directed me to the smoking generator that was ruined (solder, I think, was all over the opening in the generator from over-charging and over-heating). It was late at night on a country highway. I drove until the battery was so low that the lights were useless. The next morning, the engine started and I drove home on the battery power.
I now carry a spare voltage regulator and generator.
| | | | | Joined: Jan 2008 Posts: 4,962 'Bolter | | 'Bolter Joined: Jan 2008 Posts: 4,962 | My guess would be that the regulator stuck when you turned it off. With current going back into the generator, it tried to "motor" and of course couldn't. And something is going to burn until you have a open. Either the regulator, wires or the gen. This is why we always installed fuses of about twice the output of the gen inline with the gen wire. It was not that an uncommon occurrence. In addition to installing fuses, I was always tough to look at the ammeter when I turned an engine. We wanted to avoid a fire in a gasoline delivery truck. | | | | | Joined: Dec 2006 Posts: 720 'Bolter | | 'Bolter Joined: Dec 2006 Posts: 720 | OK, so round two for me, same issue as before just with a new regulator and a costly rebuild on my jenny. I cat afford this mess every few months, has anyone ever looked into swapping the old relay driven regulators with a solid state regulator? There has to be a SS part that will drive these old jennys. 1956 GMC 370 dump " 'Tater "1970 VW Volksrod "the Black Bomber" 2007 Chevy Avalanche 2020 Jeep Cherokee Trailhawk, 2005 Harley Davidson FLHTCUI I dig all cars, old and new, whether they were hammered out of American iron, German steel, or Japanese tin cans. Being unable to appreciate them all is missing out on a world of great things. But thats just MY opinion! :P
| | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | If indeed the cutout relay was stuck, your battery will be dead too. | | |
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