3-brush gen problems

Adam/Mill Valley CA

Adam/Mill Valley CA

Senior Member
The three brush generator on my '36 pickup recently stopped charging, it was rebuilt about 8-9,000 miles ago and has been controlled by a FunProjects voltage regulator (the one in a cutout case); this setup worked perfectly until now. The fan belt is properly adjusted. The 3rd brush was set to give about 1-2 amps charge when driving. I disconnected the B+ and armature wires from the regulator, connected them together and it shows about 10-12 amps charge (on the dashboard ammeter) when running above idle, so I'm guessing the generator is OK and the voltage reg is at fault. As best as I can tell, FunProjects is no longer in business and so I don't think a replacement would be available. I can go back to using a standard cutout but I'm wondering if there other options?
Thanks,
Adam
 
Fun Projects are still in business, but dont sell direct to the public or to Macs anymore. You can buy them off C&G Ford parts in California. Make sure you order the correct voltage and NEG or POS ground type for your application. Set the third brush to a max of about 15 amps (have to rev her up a bit for this) with the regulator out of the circuit (not connected) and then connect the regulator. Regards, Kevin.
 
The options;
fun projects regulator
original cutout
fit a diode
personally, I prefer using it the way Henry built it, simply move the 3rd brush down if driving at night, up in the daytime.
 
Thanks Kevin, that's good to know; I'll try C+G on Monday. Brian, I have no problem with adjusting the 3rd brush (and rarely drive at night) but I've been happy with the FunProjects voltage reg so if it's still available I'll probably go that route


Adam
 
I had a similar problem with my '37 1/2 ton, i installed an electronic regulator inside the generator case (the field brush will need to be removed). It works FLAWLESSLY. I found this unit through an internet search, designed and constructed by an electronics engineer, i think he's located in Ohio.
Hope this helps,
Tom
P. S. I believe the Fun Products unit is a diode type cut out with a heat sink, the unit that i installed provides full regulation and can be used with the Fun Products unit.
T. W.
 
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Fun Projects was sold to the folks at Birdhaven (also Texas T Parts). I've noticed the Fun Projects site is not available now. They were having troubles getting the IC chips like a lot of manufacturers are these days. I have no idea what is currently going on with them.

This is a link to a previous thread on the subject of regulators.
https://fordbarn.com/forum/showthread.php?t=284833
 
Hotcoupe, FunProjects may make a diode type cutout but the unit I'm referring to is a full voltage reg (with a cutout integrated into the circuitry) contained within a stock appearing cutout case. I have read of a couple of other voltage reg possibilities over on the model A side, one within the generator which replaces the 3rd brush, and another attached to the band cover at the end of the generator, and there have been positive posts about those-perhaps the first of those is what you are referring to? For my part, the FunProjects unit worked and stood up well for many years so if I can get another I'll go that route, if not I'll explore these other options. Rotorwrench I looked at the Texas-T parts site but didn't see anything relating to a voltage reg.


Adam
 
Well, contacted C+G and unfortunately they do not have the FunProjects regulator available, likewise for Joe's Antique Auto in Massachusetts. I'm going to put in a cutout, I'm not anticipating problems since the draw is low even with headlights on as I have LED bulbs in the headlights. I do have an original 1936 tube radio installed which is a bit of a draw but I don't listen to it too much since there's hardly anything worth listening to on AM radio (!)
Purely out of curiosity, and I address this to Kevin (you appear very knowledgeable about these old generators)-couldn't one disable the third brush function and wire the generator to a standard 3-terminal regulator (with cutout, voltage and current regulating functions) so that it behaves like a later 2-brush generator? Just thinking out loud.


Thanks,
Adam
 
Rewiring the generator to allow use of a standard regulator is possible, however the major drawback is it will still only have low output, so most guys going this route will simply utilise a later model generator.
And, if you fit a pulley off of a 39 std generator to the later gene, you can still utilise the stock fan.
 
I had a 3 brush generator about 70 yrs ago and it was a pain in the neck. Dumped it for a 2 brush and 3 coil regulator - more output and reliability. If you are having a judge inspecting your car and your after points, then the 3 brush gets the vote. Your call. I use a 2 brush generator and a 3 coil Borg Warner regulator, but run a ground wire between the generator and regulator in addition to the field and armature wires.
 
I found some information on John Regan's "Fun Projects" voltage regulator that delt with the components that it's made with and more than one of them are obsolete. I'm sure that there are more modern components that can be substituted but it takes a person like John that is familiar with this stuff to do that. I don't know if the current owners of the design have this capability or not.

The generators that also mated to the cooling fan were designed with front bearings that could withstand the load that the fan adds to the design. Some of the later generators may not be as robust as the OEM ones were. I heard of folks using fans mounted to alternators and then experiencing premature failure of the bearings with them. Mounting on the intake manifold also varies somewhat so that also has to be considered. I'm sure there is nothing that can't be overcome but it may take some work to get there.
 
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I have also read about premature failure of the front bearing on a later generator with the cooling fan mounted on it (which is what I would want to retain on my 21-stud motor), hence the question about rewiring the three brush gen to a 2 brush type; I imagine the voltage reg could be squirreled away under the dash or some such for the sake of appearance. I have to say, the output of the three brush has been very adequate for my purposes. If anyone has actually done this I would love to hear the details.


Adam
 
Adam,, The 3 brush 6 volt Ford generators 1934 to 1938 are capable of a safe continuous output of about 15 amps . The field wire connected to the third brush can be removed and connected to an outside insulated terminal on the generator case. The third brush is removed. A later 6 volt 3 unit Ford type regulator can then be connected to the generator.. One problem here is all of these regulators are made and adjusted to suit the later generators which are rated at about 30 amps on the current regulator and that is too high for the early generator to handle safely. The current regulator which is the center unit inside the regulator then has to be adjusted down to around 15 amps which does not always work very well. This adjustment has to be done by someone who knows what they are doing and using the older type analog gauge test set. (An Auto Electrician). I have done this modification several times and it works OK. The Fun Projects round regulators did become available again recently as I did purchase one from a dealer here in Victoria, Australia. Maybe they are just temporally out of stock. I will find out what is going on and report back. I have a Fun Projects regulator on my 34 Ford with original generator and it works very well. Regards, Kevin.
 
Kevin, thanks for the detailed explanation, sounds like the typical "turn the screw and pray" approach wouldn't work too well for adjusting the current regulator. The gentleman at C+G said they hadn't had any success getting the FunProjects regulator for some time. If you are able to find out anything else about this I would be very interested to hear it, as I'm sure would some others on this forum.


Adam
 
A fellow on the Model A section of this forum used to fabricate a voltage regulator but I believe it was a similar design to the James Peterson system. This design regulated the current to the field which required modification of the internal circuit and removal of the third brush. The current regulator was installed onto the access band which placed it inside the generator.

The Regan design voltage regulator only required that the 3rd brush be set to a specific amperage output level prior to the installation of the voltage regulator/one way diode set inside an old gutted OEM cut out can. The only thing removed was the old cut out. I think they started putting them in new cut out cans so that folks that didn't have an old original cut out wouldn't have to find one.

If a person looks at the way the later 3-brush generators are made, it becomes apparent that the brushes are not 180 degrees apart like the later 2-brush design. This likely means that not only the brush holders but the armature is also different. It would take some research and possibly some modifications of the armature, fields, brushes, and terminal placement to get an older generator converted to a two brush unit but it likely can be done. Another method would be to modify the front support on a later two brush to beef up the bearing design.

Another alternative would be to mount the generator on the head and fabricate a fan mount for the centered location. A lot of folks did this to add the dual and triple deuce fuel systems on the engine. This was a common modification for the hot rod guys back in the day.
 
Adam, It seems that Fun Projects are again unable to source an electrical component that is used inside their regulator because of the worldwide shortage of these chips. Many of the car manufactures are having the same problems of supply. It seems that we rely too much on all this electronic stuff these days. Every electrical appliance seems to have an electronic circuit controlling it. Some years ago all you had was a couple of knobs on your washing machine or clothes dryer or toaster. These regulators may not be made again for some time. We will have to wait and see. Regards, Kevin.
 
Kevin, thanks for that info, I'm not surprised given the current issues about chip supply-I suppose there would be more priority for chips for a new F-150 rather than an aftermarket piece for an 85 year old pickup, although I can't imagine why :)


I do know that 8N and 9N tractors had 6V positive ground generators of limited output (16-20 amps) and 3 component voltage regs are easily available for those, I wonder if something like that unit could work if you were to change a 3 brush gen to a 2 brush type-but understanding what rotorwrench has said about the setup of the brushes, perhaps it's not feasible anyway.


Looks like a simple cutout for my truck for the future anyway, which probably will be just fine.


Adam
 
While is is feasible, it certainly not currently an easy task to convert an OEM fan type generator. They worked for many years with a cut out. Since output is relativly low, one of the modern diodes will control back flow pretty well.

The IC chip John used was made by Texas Instruments. He started making these back in 1987. A lot of things have changed since then.
 
Well, this is embarrassing! after obtaining a cutout and running the generator with that, it turns out is actually isn't charging-i.e. the generator is the problem not the FunProjects voltage reg. I thought when I connected the the batt wire directly to the armature wire and it seemed to charge to about 10 amps that it was OK, but it seems not. Trying to have the generator "motor", it would barely move.
So, I obtained a rebuilt (used) generator from a kindly Fordbarner (F1Mike in Petaluma), installed that with the original FunProjects voltage reg, and it charges just fine (!). I took apart the original generator and the rear bushing was complete toast, and the rear spigot of the armature was totally scarred. I found a nice NOS armature for a good price, and I'll use that to rebuild the original gen, with new sealed bearings/bushing etc, to keep as a spare. Live and learn I guess.


Adam
 
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