Hi, I joined the club last year when I became owner/caretaker of a 1952 Hornet sedan. It was sitting without running for about a year or two before I got it and so I’ve spent the last year or so tuning. It’s now a solid runner with one concern I have…The generator seems to get really hot. Probably as hot as the engine block which is about 160 to 170 degrees. Is this a sign of the generator going bad? The voltage regulator gets a little warm or slightly hot but I understand it should warm up a little while functioning properly. Also, the voltage regulator is new and I did polarize when installed. Normally, I charge the battery to close to full with a charger/maintainer before driving. The thinking is I’m trying to limit how much recharging is needed and how hot the charging system will get. Most of my drives are no more than about an hour. I’d like to think the generator is doing some level of charging but I’m not confident it’s functioning properly. Restarting after driving is a little difficult. I’m not really sure if that’s a hot-start issue or due to a draining battery. Fortunately, I’ve never gotten stuck but only do relatively short drives with no more than a couple stops. I did a simple test and can spin the generator when connected to the power of the battery (removed belt and generator spins in same direction it would when motor is running). I don’t have super sophisticated electrical equipment but did put a very simple voltage-only type of meter on the generator and it seems there’s some output (although not entirely sure I’m taking a proper reading). I’d appreciate any thoughts on why the generator is so hot. That’s not normal, is it? Thank you!
It's normal for the generator to run reasonably warm due to the ambient temperature in the engine bay, but not unduly hot. Things to check: there are three wires going from the regulator to the generator, A, F, and E. Make double sure that the corresponding wires are connected to the regulator particularly the "E" wire, which is ground. This wire should be connected to the body of the generator with a small screw, and also connected probably to the base of the regulator, or some other ground connection. Make doubly sure that these wires are not transposed. If you do not have a good knowledge of the operation, or a good volt and amp meter then you really need to get the regulator set up by a knowlegable auto electrician. I cooked the generator many years ago because the E and F wires were transposed, meaning the generator was charging it's full output the4 whole time. As a rule of thumb, if you have a volt meter, connect between the A terminal of the regulator and ground, and you should get a reading of 7.2 volts with the motor revving and the headlamps on.
Thank you Geoff! The Arm and Field wires from the generator to the regulator are correct on the car. The regulator is not original but rather Standard Brand VR2/35 amp. Picture from online: https://www.oreillyauto.com/detail/c/standard-ignition/standard-ignition-6-volt-35-amp-voltage-regulator/std0/vr2
The terminals on it are Arm, Field, and Battery. Just looked at the shop manual and noticed that there’s a ground screw on the generator near the other terminals. No wire connected to it on my car. It seems that may be the problem.
I doubt it, as the generator is grounded through the mounting. You do need to check the regulator voltage setting though.
You're correct. That doesn’t seem to be the issue. My understanding was also that the generator would be fully grounded through the mounting bracket but I’m trying anything now. The regulator is specific for 6 volt usage. I’ll probably be seeking an auto electrician soon. A couple of thoughts – I should maybe rule out that there’s not something mechanical causing friction and heat at the generator. It seems to spin fine and has been lubed through the two ports. Also, I think the regulator base is making a good ground contact but maybe there’s paint or something causing an issue and I can test that too. Thanks again!
Mike ---Double check your Regulator is a "Positive Ground" type. I've reviewed the O"Reilly's link you provided on the part but I don't see that spec. I've always heard Positive Ground and Negative Ground regulators are not interchangeable. Just another thing to check...
They are not interchangeable, but will work for a while until the voltage coil points burn out. Usually stamped into the base plate.
Thank you Robert. The regulator is specified for negative or positive (shown in the picture on the O'Reilly link).
I did some more testing and tinkering. I’ll try to drive a little over the weekend and see if anything is better. I made sure there’s a good ground contact for the base of the regulator. I’m also wondering if it’s possible that my generator loses polarity. I do disconnect the battery between uses for safety reasons (still a lot of 70-year old wire and my garage attaches to the house). I’ll make sure I re-polarize at each use for now. I did some tests with my simple voltage meter which only gives me a simple digital read (e.g. 5, 6, 7 volts..no decimal). I took some readings at the battery and I see an increase as RPMs are brought up.
No, a generator will not reverse polarity by disconnecting the battery. You need to get that voltage reading of 7,2
Mike ---I now see the pic with the P or N reference but I wonder how that's done? I assume it must contain an additional circuit that senses current polarity and then switches the magnetic paths of the contacts accordingly. This is a first for me.
No, they work either way, but the voltage coil points are of different material to minimize arcing and metal transfer. If you have them the wrong way round the points will eventually burn and open circuit. If you inspect the points closely on a "single polarity" regulator you will see that one point is slightly yellower colour. On a bi-polarity the points are of a different material which will withstand arcing.
Just double checking which are the F and E posts on generator. Mine are not marked.
They will be marked (stamped into the body near the terminals). The larger post is A.
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