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Bob Wise 02-23-2011 01:27 PM

Model A Ford generator
 

My generator is not charging...what is the best way to test on the car? Not sure if the cutout is bad...

BRENT in 10-uh-C 02-23-2011 02:58 PM

Re: Model A Ford generator
 

Disconnect the Cut-out wiring and remove the Cut-out from the Generator. Next remove the fan belt. Using a set of jumper cables connected to a charged battery, connect to the Generator and see if it will spin like a motor. If so, in all liklihood it will charge and therefore consider swapping out and installing a good Cut-out with a diode in it.

.

Bob Wise 02-23-2011 03:39 PM

Re: Model A Ford generator
 

Thanks Brent!

barnstuf 02-23-2011 09:26 PM

Re: Model A Ford generator
 

Brent's advice is right on the money but I would like to add a bit of advice if you do have to buy a cutout with a diode. Buy it from a Model A Ford parts dealer and not from a flea market casual vendor. Why do I say that? It is because current goes thru a diode only one way. The Model A is positive ground. The Model T is negative ground, so the diode cutout for the A will not work on a T and the T diode cutout will not work on the A. A casual flea market seller may not know which one he is selling as they look alike.

Tom Wesenberg 02-23-2011 10:16 PM

Re: Model A Ford generator
 

Start the engine and set it to a fast idle, then jump across the two cutout terminals. If it now shows a charge the cutout needs the contacts cleaned, or the pull in winding is bad. If the amp guage still shows a charge after the jumper wire is removed, then the generator just needed to be polarized.

Don't run a Model A generator for more than a few seconds if it's not connected to the battery, or it may burn itself up. If the cutout is faulty, then the generator isn't connected to the battery. In case of a faulty cutout, you can safely run the generator by jumping the output post to ground.

Bob Wise 04-16-2011 09:38 AM

Re: Model A Ford generator
 

Removed the cut-out, fan belt and ran a jumper from the starter cable (neg) to the post on the generator and got a spark...looks like the generator is shorted and needs attention...I also have lost two condensors during the time that the generator was not charging.

joeflh 11-24-2013 05:44 PM

Re: Model A Ford generator
 

Thanks to all of you got the old 31 ford charging again
Joe:cool:

Bruce of MN 11-25-2013 07:28 AM

Re: Model A Ford generator
 

Quote:

Originally Posted by Tom Wesenberg (Post 166506)
Start the engine and set it to a fast idle, then jump across the two cutout terminals. If it now shows a charge the cutout needs the contacts cleaned, or the pull in winding is bad. If the amp guage still shows a charge after the jumper wire is removed, then the generator just needed to be polarized.

Don't run a Model A generator for more than a few seconds if it's not connected to the battery, or it may burn itself up. If the cutout is faulty, then the generator isn't connected to the battery. In case of a faulty cutout, you can safely run the generator by jumping the output post to ground.

Is the procedure any different if you have a diode cutout (bought from a major shop)? My gen motors, but doesn't give more than battery voltage at a fast idle and the 3rd brush pushed all the way down.

Tom Wesenberg 11-25-2013 10:26 AM

Re: Model A Ford generator
 

Quote:

Originally Posted by Bruce of MN (Post 772114)
Is the procedure any different if you have a diode cutout (bought from a major shop)? My gen motors, but doesn't give more than battery voltage at a fast idle and the 3rd brush pushed all the way down.

Same procedure for the diode cutout. Jump the two terminals with the engine at fast idle, then if it still shows no charge the generator most likely needs to be repaired. Check the voltage with a seperate meter to see if it rises above battery voltage.

Bruce of MN 11-25-2013 11:19 AM

Re: Model A Ford generator
 

Thanks, I'll do this.. I always thought that motoring was a reliable sign that the generator was OK.

Quote:

Originally Posted by Tom Wesenberg (Post 772196)
Same procedure for the diode cutout. Jump the two terminals with the engine at fast idle, then if it still shows no charge the generator most likely needs to be repaired. Check the voltage with a seperate meter to see if it rises above battery voltage.


youngs1 06-14-2015 09:43 AM

Re: Model A Ford generator
 

Quote:

Originally Posted by Tom Wesenberg (Post 166506)
Start the engine and set it to a fast idle, then jump across the two cutout terminals. If it now shows a charge the cutout needs the contacts cleaned, or the pull in winding is bad. If the amp guage still shows a charge after the jumper wire is removed, then the generator just needed to be polarized.

Don't run a Model A generator for more than a few seconds if it's not connected to the battery, or it may burn itself up. If the cutout is faulty, then the generator isn't connected to the battery. In case of a faulty cutout, you can safely run the generator by jumping the output post to ground.

Tom, you were right on the money for my French-assembled 29 Tudor's side cutout Powerhouse generator about the polarization. Had a loose field coil that caused a break in the solid wire connection between two of them. Placed a crimp collar across the break and used a pencil soldering torch from Harbor Freight to run some solder down into the collar connecting and stabilizing the break. Motor test off and on the car were fine. No charge when started, however. Had left the back cover off and connected the jumper across the diode cutout I have installed. Some sparks came from the engine side of the back of the generator and I now have good charge level. Believe polarization was the problem. Another one for the mind file of tips and tricks. Thanks for posting here where we novices can find them.

redmodelt 06-14-2015 01:59 PM

Re: Model A Ford generator
 

"Is the procedure any different if you have a diode cutout (bought from a major shop)? My gen motors, but doesn't give more than battery voltage at a fast idle and the 3rd brush pushed all the way down."
OK, but what is the AMP's it's putting out?

Tom Wesenberg 06-14-2015 08:21 PM

Re: Model A Ford generator
 

Quote:

Originally Posted by redmodelt (Post 1103121)
"Is the procedure any different if you have a diode cutout (bought from a major shop)? My gen motors, but doesn't give more than battery voltage at a fast idle and the 3rd brush pushed all the way down."
OK, but what is the AMP's it's putting out?

You polarize the same way with a diode cutout. The amps output should show on the instrument panel ammeter, and if you have the 3rd brush pushed way down, the output should be quite high.

walt jones 06-14-2015 10:05 PM

Re: Model A Ford generator
 

Usually motoring a generator provides a good indication that the generator will do its job and generate, but not always. I had a power house generator that would motor fine but when the generator was put in service it would fail to provide sufficant current for charging. A growler test of the armature showed that it had a shorted winding. Hopefuly yours does not have this problem.

All the best,

Mike V. Florida 06-15-2015 12:03 AM

Re: Model A Ford generator
 

Quote:

Originally Posted by BRENT in 10-uh-C (Post 166247)
Disconnect the Cut-out wiring and remove the Cut-out from the Generator. Next remove the fan belt. Using a set of jumper cables connected to a charged battery, connect to the Generator and see if it will spin like a motor. If so, in all likelihood it will charge and therefore consider swapping out and installing a good Cut-out with a diode in it.

.

If you apply voltage to a generator it will try to work as a motor. This is the reason for the cutout, it cuts the generator out when the engine is not moving (or moving fast).


If it doesn't motor it is an almost guarantee that the genny is bad. Like Brent says in all likelihood the genny will work. Next step after the genny motors is to follow Toms advice;

[quote]Start the engine and set it to a fast idle, then jump across the two cutout terminals. If it now shows a charge the cutout needs the contacts cleaned, or the pull in winding is bad. If the amp gauge still shows a charge after the jumper wire is removed, then the generator just needed to be polarized.[/unquote]

This actually does two things, bypasses the cutout, and polarizes the generator. WARNING if you have a regulator in a can and not a cutout you will damage the regulator.

Just wanted to put all the steps in one post with a little explanation.


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