Wax in a generator?

Stingray70

Stingray70

Senior Member
Dripping from it actually. I just came back from a 50 mile drive after installing a rebuilt generator and there is almost a tablespoon of red wax that has run out of the bottom of the generator and dripped down on the splash pan. I can call Snyders next week but was curious if anyone here has any thoughts?
 
I can't think of anything that would have wax on it inside a standard 3-brush generator. I'm not sure about an older powerhouse type generator. I don't know what generator you have or if it has a cut out or voltage regulator on it.

It takes a bit of heat to get wax to melt but a functioning unit will get fairly warm in operation. If the battery is not well connected then it can overheat due to over-volting. The battery is the voltage regulator for a 15-amp 3-brush generator. A bad connection is hard on the system and can damage the generator.
 
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It is a late 30 style generator with the diode cutout. Good battery, new cables, zero corrosion. I have the charging rate set at 6a. Generator didn't seem excessively warm after the drive.
 
Sometimes they paint the windings inside the generator with red paint, could this be leaking out for some reason?
 
If it is a dark red, almost maroon, it may be the insulating varnish or paint used to insulate the windings. Glyptol is frequently used by motor shops for this purpose. Perhaps the varnish wasn't thoroughly dry and broke down with heat. Whatever it is, it should not have happened. Let your vendor know about this.

John
 
While paints & varnishes may burn at a certain temperature, I've never seen them melt. Glyptal and magnet wire varnish both dry relatively quick and have a good history with electrical motors and generators in normal operation. Both were designed for that specific purpose. Glyptal is also used inside a lot of cast iron engine blocks and transmission cases with good results over time.

I have no idea whether Snyder's rebuilds any of their electrical cores or not but they might do that or send them out to a trusted electrical rebuilder. Some of the internal replacement parts may be from offshore or out of US sources but most I've seen look normal for construction and materials.

There are more than a few synthetic clay soap type red greases that are available now days and they can melt and run but thicken back up after cool down. I'd suspect something like that more than a parafin type material.
 
Update:
I spoke with the vendor today. I have always been impressed with their customer service. They spoke with the rebuilder who said this is an insulator material. They assume the generator overheated and are sending a replacement. So that is the answer but my new question is why? What do you guys set your 3rd brush to?

Here is a picture of about 2/3 of the wax that I pulled off the bottom of the generator and splash pan. This is about a teaspoon full.
 

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Grounding could be a problem that might cause heat buildup. When the ground is nominal, the system "SEARCHES" for better ground and heat develops. In the case of a generator, this can be nothing more than too much paint on the mounting brackets or the mounting boss where the generator mounts on the front timing cover. When I rebuild a generator, I'm extra fussy about the ground between the front and rear plates and the generator case and even between the rear mounting bracket and the case. Assuming that all of those places were blasted in your rebuild, those areas should be OK. When you get the replacement, sand the paint off the mounting points to bear metal. If you're concerned about rust developing, a very light (VERY LIGHT) coat of grease won't hurt.

As per the charging rate, unless you plan lots of night driving, 6-8 amps at high RPM should be plenty and should stop any other overheating scenario in the generator itself. Of course, we also need to assume the rest of the wiring, electrical contacts, battery cables, and battery itself are up to snuff. If you've purchased a rebuilt generator to solve other electrical issues, you're working backward.

Good luck.
 
As in the post above, the whole battery and generator circuit has to be in good low resistance condition and that included both the conductor wires and the ground path. There may have been a high resistance connection inside the generator but do check all the wiring and ground path points of connection to insure the longevity of the generator. A loose wire in the terminal box or on the ammeter can be a problem too.

A freshly overhauled generator will also need to be polarized to get good residual magnetic gauss in the field pole shoes.
 
Thanks for the replies gentlemen. My wiring is in excellent condition (I have been through every inch of it) but I didn't think to check the mounting bracket for paint. Never had trouble before. I'm only switching from an alternator installed by PO back to the correct original generator.

I was surprised that the vendor said that 6a would cook the battery. He said their preset 2a is correct. Doesn't sound right to me. Les Andres vol. 1 says 8a-10a. That actualky seemed high so I went with 6.
 
A voltmeter in addition to your ammeter is your friend. The voltage regulator on a Model A is the operator, like many of things that are manual on a Model A but automatic on a more modern car. With a voltmeter you can check the charging. The battery voltage should be about 7 volts when the car is running. At night you will have to set up the current to maintain that charging voltage. Before you start your car you can check the voltage to see if the battery is in good condition. It should be 6.2 volts or more after sitting over night. The Ford dealers would check the electrolite specific gravity in the batteries when the car came in for service and would adjust the charging current accordingly. The voltmeter is a easier than checking the electrolite.
 
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The operator can adjust for current output, which can affect voltage to some degree, by 3rd brush movement. The battery is the voltage regulator in a three brush system.

There have been several solid state regulator designs made for the old three brush generators but I'm not sure if any are being produced at this time. Fun Projects can't get the IC chips that John Regan used anymore so that stopped production. The regulator makes for a much more efficient generator. A standard three brush tends to put out more than the battery need in some cases or not enough in others.
 
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Stingray70 said:
What do you guys set your 3rd brush to?
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Around +8 to 10 amps without lights, brake or indicators on. That translates to around +1 to 2 amps with lights on.
If I think the battery is fully charged I just turn on the lights. Driving mostly on country roads with lots of (often kinda dark) forests turning the light on can't be wrong with this car.
 
What I was trying to say is that a three-relay regulator connects to a generator that has an external Field post, which the A generator does not have. Its field connects to the third brush.
 
As was already mentioned, the 3-brush would either have to be replaced with a later type 2-brush generator like the Ford tractors used or modified into a 2-brush generator circuit set up. John Regan's set up just replaced the cut out with a voltage regulator and diode circuitry inside of a cut out can. The 3rd brush was nominally adjusted for operation and then left alone. The voltage regulator types that were made to fit inside the generator required internal modification of the generator circuit such as James Peterson's design. It replaces the 3rd brush but can still use either a cut out or a power diode. This is a link to the A/B Ford Garage on the subject. https://www.fordgarage.com/pages/generator.htm

I'm not sure if this one is still in production or not. The VR controlled generator will run cooler and with less drive power than the always working 3-brush unit will. It can take a rest after the battery is fully charged as long as the lights are off. Running power to the ignition coil doesn't strain it very much.
 
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