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I have been collecting parts to rebuild a 1938 HA passenger car generator model #1100004. I have an NOS armature #1871826 and NOS field coils #1902105 and a set of brushes. I have two identical fan type pulleys with no numbers one of them was on the used generator when purchased. Does anyone have info for a source to obtain the two studs with insulators? Are all the external parts including the fan pulley and band painted black? Other than the pulley bearing and armature rear bushing what other parts should be replaced. I have not decided whether to rebuild myself or take the parts to an antique generator re-builder. Any one have any suggestions on how to approach the rebuilding of this unit to bring back to like new condition? Thanks, Jim

If you are not totally comfortable with rebuilding the generator an experienced professional is probably your best bet. Professionals should have the disassembly, test, assembly and installation equipment to do the job right. The cost should not be prohibitively expensive. However if you want to tackle the job yourself it is not too hard but changing the bushings can be a bit troublesome. Re-wrapping the field coils can be a problem. Also knowing that you have the proper spring pressure on the brushes can be tricky. Right Skipper?

Right Chipper!

Re-wrapping the field coils for me is not a problem since I have re-wrapped many of them for my customers in the past.

The GM replacement coils are already wrapped out of the box and ready to install. The generator seems like an easy rebuild since the armature is also new and bearing and bushing are easy to find. The felt wicks and gaskets would be nice to find but could be made. I could try to salvage the two studs and insulators from some other old GM generators I have but finding new ones would be good. One of the studs on the 1100004 generator I'm rebuiding has stripped threads. Any ideas on were to find them? To remove the pulley nut which was pretty tight I heated the pully and applied penetrating oil. I used an old belt wrapped around the pulley and clamped in a bench vice to hold the pulley so i could take off the nut without damaging the pulley. I haven't dissambled the generator yet but it looks like the third brush is fixed? I would think with a voltage regultor instead of a cut-out voltage is adjusted at the regulator and not at the third brush?. As to color are housing, back plate, band and pulley all black. The housing has a nice tag so that is good. Any other good tips on working on these units?

Just so you are aware brush spring pressure is also a specification that you should be aware of. Thought Skipper would pick up on that but must be his eyes were not completely open this morning when he posted his reply.

Wow Chipper......you are the one with your eyes closed! First, I didn't make the post that you are referring to this morning....I made it yesterday evening. Second, I responded to your spring tension question by posting "Right Chipper".

videoranger: Regarding your generator, you can get all of the parts that you listed at your local starter/generator shop.

How about the paint specs for the items mentioned for a 1100004? Skip, can you provide more info on the spring tension setup? Is the third brush fixed? Never rebuild an old generator before so i want to be prepared with parts and sufficient info before starting the project. thanks

The generator housing, both end plates and the pulley are painted black. The third brush is fixed. The spring tension for the main brush is 22-26 ounces. The tension for the third brush is 16-20 ounces. You will need to use a spring tension gauge to get an accurate ounce reading.

Be sure to polarize the generator when installing.

Thanks, thats good info to know. I'm assuming the band is black also. I know of some small re-build shops that have experince with the old generators that I think I can go to for parts and maybe they can help set brush spring tension and test the generator for me. Any more on how the spring tension is adjusted and if it's done before or after the armature is in place or if it's done before the brush holder is installed? I also need to find the belt tesion bracket since I can't seem to find one in my parts stash. I have a couple of the generator mount brackets that bolt to the block. Are the mount and tension brackets black also?

I believe that the brackets are painted engine color.

The spring tension is checked before the end frame is installed on the generator, and with the brushes and the brush holders in place. You can adjust the spring tension by bending the arm on the spring. If a spring is weak I always replace it with a new spring instead of adjusting the old spring.

Didn't they stop using cutouts in late 37 and started using regulators in 38?

The brackets are painted black. If I remember correctly the band was not painted. It had the bluing treatment.
All 1937's came with a cutout but there was a voltage control option same as a 1938. The voltage control option began in about 1933 or 1934. Was more or less necessary when a radio was installed and the owner wanted to use the radio and had the head lights and heater on.

Thanks again for all the very helpful replies! It's been a long process for me getting all the parts together and repair and rebuilding going on my 38 coupe, but I really want to see this car done as original as possible. Web chats aren't the easiest way to communicate but our VCCA guys with lots of experience sure help to sort through the details.