VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 38 Generator

My generator stopped working so I took it out of the car and checked the coils, the armature, everything. It all checked out so I cleaned it up a little and put it back in the car. I started the car and the meter was full on C on the ammeter. While I was patting myself on the back I hit the gas and the charging stopped. I stopped and started the car and the charging was back. I waited a couple of minutes and turned on the head lights, the charging stopped. I turned the car off and started it again, the charging started then stopped. A couple of more times and the charging was gone completely.

I decided to do some voltage regulator tests so I started the car, put it up to 35 mph speed and grounded the field terminal of the regulator, the charge came back. I stopped then started the car and the charging was gone. I made adjustments to the regulator and they had no effect on the charging rate.

Does this make sense to anyone?

Brain

If you ground the field terminal and it charges the generator is good and the reg. is bad.After you grounded the fields and it charged did you try grounding the fields again to make it charge?If so did it not charge/You some what lost me on that one.
If it not charging it usually is not corrected by adjusting the voltage regulator.
I could send you a different reg. to try.

I did try again to ground the F terminal and nothing happened, a couple of times. The whole ordeal was as if I had fixed the generator but only momentarily and now the generator is bad again. I thought about it last night and was wondering if the heat could have an effect on the function of the generator? Or could it be that there is some sort of wear problem, maybe stuff collecting in the armeture grooves? Those are the only changes that occured. I did "motor" the generator as the last part of the test and it did motor at about 3 amp. Can I move the A connection on the generator so that it is attached to the brush not directly opposite the ground? Will that tell me anything about the generator?

I have a couple of meters and a variable resistance and could test the regulator, if that could really be the problem. It was out of the box a year ago so I don't beleive it is the problem. I did try to adjust the points, first open then close, to see if that had an effect but it didn't change anything so I returned them to original location. The problem is that every test drains the battery.

The battery has held a charge all winter so I know there is no bleed to ground. It's just a little frustrating.

Brian

I had a similar problem on my 47. Alot like you stated. After alot of frustration, and a NOS regulator. I decided to tear down the generator. I found that one of the tiny wires that connect the field coil to the terminal was broken. I re-soldered it, and its been working great since. It was shifting, sometimes making contact, and sometimes not. Just something you may want to check?

You know, the wire break might work with my heat theory also. I was going to take it out tomorrow and reinspect the components. I'll add that to the list of possible problems, run the usual tests, and see where that takes me. There must be something wrong with it that I missed. I can't believe the regulator is part of the problem it is (and looks) brand new.

Brian

I took the generator out and it motored at about 3-4 amps. I took it all apart and everything checked out as fine, no short in the armature, balanced field coils, no short in coils, and put it back together and it motored at 3-4 amps. Put it back in the car, sparked it to polarize, and nothing.

What am I missing?

Brian