Generator woes

[Rex_A_Lott]

I have a "rebuilt" generator that doesnt charge. I've had it off and it will motor, slowly, in the correct direction. In fact, it will motor ( because the belt is too loose) after the engine is shut off. I thought that maybe the cutout was sticking, but after the battery is disconnected it quits (of course). After reconnecting it again, it doesnt motor, until after the engine is ran again, then its the same scenario.
While the engine is running, the stud at the front of the cutout, where the generator output is supposed to be, will measure about 9 volts, but the other side of the cutout, where the battery is connected, wont measure anything. However the ammeter will show about a 10 amp charge rate, even though it doesnt seem to be charging the battery.
With the engine off, there is no continuity from the output stud to the battery connection on the cutout, which to me means its not sticking. There is continuity from the output stud to the two mounting screws on either side. I dont see how this can be correct, but I'm not sure.
Any help will be appreciated!

[Tom Wesenberg]

Run the engine at fast idle, then use a jumper wire between both sides of the cutout. Does the ammeter now show a charge?After this check remove the jumper and stop the engine and read the voltage at the generator stud and ground. What is it?

Sure seems like a bad repro cutout.

[Rex_A_Lott]

Originally Posted by Tom Wesenberg

Run the engine at fast idle, then use a jumper wire between both sides of the cutout. Does the ammeter now show a charge?After this check remove the jumper and stop the engine and read the voltage at the generator stud and ground. What is it?

Sure seems like a bad repro cutout.

With the hand throttle about halfway down, the ammeter bounces around between 10 and 20. After I put the jumper around the cutout, it seemed to be more steady around 18. After I shut it off, I measured around 4v at the generator stud. If I pulled enough slack in the belt, the generator would motor, and the volatage reading would go up to about 5.2.
So with that, I guess the cutout is sticking after all ?
I'm open to suggestions about a replacement ( diode?) and a source for a quality one. I grew up in the era where if you needed a good electrical part you went to NAPA and asked for Echlin, but I havent checked to see if they make Model A parts...and I'm pretty sure even if they do they dont have enough demand to stock them locally.
Thanks for your help Tom.

[Tom Wesenberg]

Bert's has restored original cutouts or you could use a diode cutout.
A&L makes quality diode cutouts and they and some of the parts houses sell them.
I always use a restored original cutout and never have had a problem.
BTW, it seems your generator is adjusted for too much output. I wouldn't set it for more than about 2 or 3 amps, unless you do a lot of short drives, then maybe 5 amps.

[Rex_A_Lott]

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Originally Posted by Tom Wesenberg

Bert's has restored original cutouts or you could use a diode cutout.
A&L makes quality diode cutouts and they and some of the parts houses sell them.
I always use a restored original cutout and never have had a problem.
BTW, it seems your generator is adjusted for too much output. I wouldn't set it for more than about 2 or 3 amps, unless you do a lot of short drives, then maybe 5 amps.

Thanks Tom. One of my other A's was converted over to 12v and an alternator, and the other is still original 6v +ground, but I've never had any trouble with it, so all this stuff w/ the generator/cutout is new for me. Once again my education is costing me money, but at least I know I get good help here at the Fordbarn!