MTFCA Forum

I am continuing to straighten out a friend's newly-acquired 1925 Coupe's mechanical and electrical issues. The patient is finally on the road to recovery!

One lingering problem concerns the generator. Even after installing a new wiring harness, unless I polarize the generator upon each start, the generator will not show a charge on the ammeter after the next start. Polarizing it again starts the charging. In other words, after polarizing, the generator charges nicely while the engine is running. Shut off the engine and the next time it is started, no charge until the generator is polarized again. This happens every time, darn it! Does this sound more like a cutout issue or does the problem lie in the generator itself? Why must be it be polarized EVERY time when the engine is started? A new head scratcher for me...

Marshall

After the engine is keyed off, is there a reading on your ammeter other than " 0 " ????

Do you have a stock type cutout?

Marshall
Could be the cutout or the generator.
Replace the cutout with a known good one. If that fixes the trouble, great.
If not, the problem is inside the generator and could have several different causes.
If this is the case give me a call tomorrow and I will explain in detail the internal generator starting up process (called 'building-up") and understanding how this works will give you some clues where to look inside the generator for the cause of your problem.
Ron Patterson
231-348-5085

Thanks for the replies so far. I'll try a couple tests and parts swaps before I turn to the "big guns" for advice (Ron Patterson).

The ammeter returns to zero when the engine is shut off. Strangely, the ammeter shows a charge, but will not dip into the negative zone when the lights are turned on and the engine is off. I connected the linking wire from the ignition switch to the ammeter per wiring diagram, meaning to the negative terminal. Maybe I should try connecting it to the positive one? The new battery is grounded from the negative terminal.

The cutout appears to be an original style. I haven't removed the cover to examine its innards, but because I can repeatedly polarize the generator and register a charge on the ammeter (apparently without damaging the cutout), I assume a diode must not be contained inside.

I'll see if I have any operating cutouts in my stash of old electrical parts. I was hoping someone here would point to a smoking gun based on a similar experience and say the cutout is to blame for sure or the generator is the problem. I'll report back what I find in a few days.

Marshall

A stuck Ford cutout would show a heavy discharge and run the battery down fairly quickly with the engine off. A diode cutout might leak some reverse current and cause your issue without causing other immediate issues.

I think the problem is in the generator. I have one similar except that when I first start it I polarize it but if I stop for gas or elsewhere and start up again it doesn't need to be polarized. In fact sometimes if I start driving after about a mile, the ammeter will show a charge!
Norm