Generator on the fritz

[Killerbee]

I have a generator on the fritz can’t get it to charge and it’s driving me nuts. So far I’ve replaced the brushes, fields, cleaned and tested the armature. No shorts on the armature and ohm out all the commutators. Everything ohm out good. I can bench test the generator with a drill and get 6.5 volts out of it but when I put it on the car I get nothing.Drill and engine are spinning it in the same direction only the car spins it faster. Take it off the car spin it with the drill again and get the same 6.5 volts. What an I missing here? I’ve had it on and off the car a half a dozen times. Its not the cut out and it is wired correctly. Before I drop $100 on a new armature I figure I’d see if anyone else had this issue

[Big hammer]

Add a temporary ground from the generator case to the car frame and check for voltage

[Killerbee]

Did that with no success. It doesn’t make any sense why it would work on the bench by just spinning it with a drill. It’s been in the trash once and fished out next time it staying there. That’s the level of frustration with it now.

[quickchange]

Give Brattons a call they have fully recon ones at an unbelievable price, How do I know well I bought a sack full few weeks ago ,

[tudor87]

Had a similar problem which turned out to be, there was not enough gap between the stator and armature. Thanks to help I got from others on fordbarn, I took the screws out that was holding the fieldcoils and replaced them with bolts and tightened with pneumatic tool. Lost about a week before I found this problem. Good luck.

[Killerbee]

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Interesting. I couldn’t get the armature in with the new fields using the new screws. I did put bolts in just to pull them in a bit then put the screws back in. I’ll give that a try tomorrow.

[tudor87]

I had to use an impact wrench to pull the field coils in to get enough clearance. That was the last thing I did after going thru the generator 3 times trying to find the problem. Again, good luck to you

[Mike V. Florida]

Cut out seems to be bad or misadjusted.

[Tom Wesenberg]

When it's on the car with the belt off, put voltage to the output post and let us know what direction it spins. If it spins opposite normal direction, then the field windings are on the wrong side.

[Patrick L.]

Once a generator is apart for repair [ especially the coils] it'll need to be polarized/flashed.

Start the engine and take a jumper wire and touch across the 2 cutout terminals for a nano-second. See if that helps.

[Killerbee]

No DC before the cut out so it’s not that. On the car with 6 volts from the battery it does spin in the same direction as the engine. Polarized while engine running to try to jump start it and no dice. I’m done messing with it it’s going to a someone that rebuilds them.

[Railcarmover]

I took the generator off of my fritz and ran an alternator..



If your generator 'motors' in the same direction as the engine turns then it will charge, changing the generator won't cure the issue.you have to rev the engine up above 1500 rpm or so before the cut out drops in.

[BILL WILLIAMSON]

Refusing to give up, is a VIRTUE, only up to a point,
Learning WHEN to give up is the beginning of WISDOM!
Bill W.

[Killerbee]

Originally Posted by Railcarmover

I took the generator off of my fritz and ran an alternator..



If your generator 'motors' in the same direction as the engine turns then it will charge, changing the generator won't cure the issue.you have to rev the engine up above 1500 rpm or so before the cut out drops in.

You should still have dc voltage before the cut out. I’m checking for voltage directly out of the generator if I rev the engine not difference. I’m thinking my armature is bad. I just don’t want to drop $100 for it not to fix the problem. Now that I have money into it I don’t want to just exchange it for a rebuild one. If I would’ve done that in the beginning it would’ve only been $50 more than what I’m going to have into it. Plus less aggravation. I have a alt on the car now but want a working generator to put on it for other reasons.

[Crankster]

If you motor a generator, no need to polarize, it accomplishes the same thing.

[Tom Wesenberg]

It motors, so the generator ground is OK, and the output wire isn't grounding out.

Slip a piece of paper under the adjustable brush (which MUST go to the field windings), then connect a battery charger + ground and - to the adjustable brush, and see if you get about a 4 amp reading.

[katy]

Try washing the commutator and brush faces w/a good degreaser.

[Railcarmover]

Ive been fooled by a voltmeter before. you get a good voltage reading but you don't know the actual capacity of the circuit. I still say your generator and armature is good due to it motoring. humor me, motor the generator with the cutout hot wire...wonder if your hot wire is falling out under load.

Try what Tom says too...

[Killerbee]

Originally Posted by Railcarmover

Ive been fooled by a voltmeter before. you get a good voltage reading but you don't know the actual capacity of the circuit. I still say your generator and armature is good due to it motoring. humor me, motor the generator with the cutout hot wire...wonder if your hot wire is falling out under load.

Try what Tom says too...

That’s how I’m motoring it with the arm wire feeding the cutout. All wires have been replaced. I’m convinced it’s the armature but now I can’t get it out of the case lid. I don’t see any clips that hold it in and don’t want to crack the lid.

[Killerbee]

[QUOTE=Tom Wesenberg;1547492]It motors, so the generator ground is OK, and the output wire isn't grounding out.

Slip a piece of paper under the adjustable brush (which MUST go to the field windings), then connect a battery charger + ground and - to the adjustable brush, and see if you get about a 4 amp