My Generator won't Generate

[Robbie Horn]

I polarized it. I put a jumper wire across the cutout terminals & still no increase in voltage. I moved the 3rd brush both ways and no difference. Pretty sure I need a complete generator rebuild & probably a new cutout. I really want to keep the generator, but its not looking good. I looked in the classifieds for a good used one & didn't have any luck. What is the best way to fix this? Send it to Snyders for a rebuild & buy a new cutout?

[Synchro909]

I have a couple on the shelf. Come and get one

[Rob Doe]

If I remember correctly, the Les Andrews blue book, "Trouble Shooting and Diagnosis" tells how to test the cutout and the generator output with a VOM on pages 2-30 and 31. You might only need a cutout.

[ndnchf]

If you polarized the generator and it motored when you did it, then your generator is most likely good. I refurbish original Ford cutouts. I can refurbish yours or sell you one outright. PM me if interested.

[Robbie Horn]

Originally Posted by ndnchf

If you polarized the generator and it motored when you did it, then your generator is most likely good. I refurbish original Ford cutouts. I can refurbish yours or sell you one outright. PM me if interested.

My generator will not motor/run & my cutout is not a OEM. I need both generator & cutout. I've never rebuilt a generator but I might try it. Don't know if I want to try it or send mine off & have it rebuilt.

[ndnchf]

Sponsored Links (Register now to hide all advertisements)

Contact Buckeye Auto Electric for a rebuild. They do them for Snyders and others. I can help with the proper original cutout to match the month/year of your car.

https://www.buckeyeautoelectric.com/contact

[rotorwrench]

I assume that this is a later Auto-Lite type generator. The older power house types can be difficult depending on condition but the most difficult repair on an Auto-Lite type is replacing the field coils if needed. A person either needs a growler or know a local shop that may have one in order to thoroughly test the armature. The armature may need the commutator turned if it's rough which also requires undercutting the mica between the segments. Most other things are fairly easy for the DIY guy. A lot depends on condition.

Many times all that is needed is a good cleaning and replacement of the worn brushes & bearings. The est way to polarize the pole shoes is to perform that before reassembling the generator. The field is shunt wound with one terminal on the 3rd brush and the other in contact with ground on the case. To get residual magnetization in the pole shoes. a person needs to use a 6-volt battery and two jumpers to perform that task. Jump the negative lead off the battery to the field wire that will attach to the 3rd brush then jumper the positive lead to the generator case for a moment. It only takes a moment to magnetize the pole shoes using a strong DC power source. Once they are magnetized with the correct polarity then the generator can be reassembled, Motoring the generator to polarize is not all that good for the armature or the three brushes since the power has to flow through all that on a series wound generator to get it to motor. Flash it with full battery power and the residual magnetic gauss will be stronger in the pole shoes.

In magnaflux procedures, a large coil and DC current supply (usually one or more large batteries) is used to magnify a part with straight line polar magnetism. One end of the part is north and the other south. Large copper plate contacts are pressed against each end of a part to realize circular magnetism in that part. This allows to check for both longitudinal cracks and cracks that are radial to the axis of the part. A large AC coil is used to demagnetize the parts after completion of inspections. The residual magnetism in the pole shoes is what allows the generator to gain enough power output to get the cut out to close and bring the generator on line.

[Patrick L.]

So you removed or loosened the belt and fed power to the generator, and, it wouldn't motor ? Well, if so, it needs to come apart.

[katy]

I ordered a set of field coils on August 25th, was told they were on back order and they expected delivery in 7 - 10 days. Emailed the vendor (Mike's) last week and was told they're still backordered.
Therefore: Still waiting.

[Conaway2]

Originally Posted by Robbie Horn

My generator will not motor/run & my cutout is not a OEM. I need both generator & cutout. I've never rebuilt a generator but I might try it. Don't know if I want to try it or send mine off & have it rebuilt.

There are videos and articles available that describe rebuilding a Model A generator. If your generator does not have that ‘burned electrical’ smell to it, chances are you just need to clean contacts and perhaps replace brushes.

Disassembly and cleaning is fairly easy to do. Visually check the insulation on the field coils. Many times, the field coils are good, but the original cloth
Insulation is shot. You can re-wrap the coils with Scotch fiberglass tape and they will be fine for many years. However, removing the field coils can be difficult without a special tool.

The commutator contacts on the armature may need cleaning as well - again, fairly easy to do.

Take it apart and post some pics - you’ll get lots of help here.

Good luck - Jim

[ndnchf]

Originally Posted by katy

I ordered a set of field coils on August 25th, was told they were on back order and they expected delivery in 7 - 10 days. Emailed the vendor (Mike's) last week and was told they're still backordered.
Therefore: Still waiting.

If the field coils are not internally shorted (which is usually caused by the magnet wire's insulating coating deteriorating), they can be rewrapped and rewired. I do this quite often. The link below is to a generator rebuild series I made for a 1940s Willys jeep generator, but the principles are the same. Parts 6 and 7 discuss the field coils and rewrapping.

https://youtube.com/playlist?list=PL...Mt1HpMpMhiSOsR

[ndnchf]

These are model A generator coils I rewrapped and rewired.

[ndnchf]

I'll add one more thing. Removing and replacing field coils and pole shoes is not easy - they are very tight and need to be. There is only about .010" clearance between the armature and pole shoes, so the pole shoes must be fully seated and tight. I used to use an impact screwdriver and big hammer. That works, but its tricky. I have since built a rig to use in a 3 ton arbor press that works great. Also, using a exhaust tailpipe expander really helps to seat the pole shoes and form the field coils if needed.

[katy]

ndnchf, thanks for the tips.
The pole shoe screws on my generator have a square recess in them, smaller than 1/4" but larger than 6mm. I ground down a hex bit to fit and used it similar to your 2nd picture in a small hydraulic press w/a good inside support. I have 2 exhaust pipe expanders, will have to check if the larger one is big enough.

[ndnchf]

Originally Posted by katy

ndnchf, thanks for the tips.
The pole shoe screws on my generator have a square recess in them, smaller than 1/4" but larger than 6mm. I ground down a hex bit to fit and used it similar to your 2nd picture in a small hydraulic press w/a good inside support. I have 2 exhaust pipe expanders, will have to check if the larger one is big enough.

I believe those square recess screws are a later replacement. But nothing wrong with them if you have a tool that fits them. The tailpipe expander I use came from Harbor Freight. Inexpensive and works great.

[nkaminar]

Most likely you just need to replace the brushes, a fairly simple job. Maybe also clean the commutator.

A good motor/generator shop, if you can find one these days, can rebuild you generator.

If you need to remove the field windings, clamp the shoes to the case with two strong clamps. This will take the strain off the screws and allow you to remove them easier. Do the same when re installing the shoes.

An ohm meter is very handy to check out the continuity of the windings and armature and the general health of the generator. Just use simple electrical logic.


Katy, I was responding to the original poster, Robbie Horn. But feel free to use the clamps technique for removing the shoes.

[katy]

nkaminar, you replying to me?
Nothing wrong with the brushes or armature , field windings meggered NG.

[ndnchf]

Originally Posted by katy

I ordered a set of field coils on August 25th, was told they were on back order and they expected delivery in 7 - 10 days. Emailed the vendor (Mike's) last week and was told they're still backordered.
Therefore: Still waiting.

Synder's shows the field coils in stock:

https://www.snydersantiqueauto.com/p...5995&cat=41710

BTW, they are made by Wilson Auto Electric, PN 56-02-4406 coils. Wilson's website: https://wilsonautoelectric.com/

[rotorwrench]

The square drive pole shoe screws might be a Canadian thing. Robertson screws come to mind.

[Gene F]

Hmmmm. Got in my A a couple years ago, and all the sudden the thing was charging zero. Is it likely to be a cutout, or brushes? (powerhouse) I have a standard generator now.

[katy]

Originally Posted by rotorwrench

The square drive pole shoe screws might be a Canadian thing. Robertson screws come to mind.

Could be, but it's an American vehicle, I bought it in Montana.

[nkaminar]

Gene F, Use your trusty volt meter to measure the voltage at the generator output post while the engine is running. If zero then the generator needs attention. If not zero then the cutout needs attention.

[Gene F]

thanks

[TerryO]

My generator won't gen, my carburetor quit carbing and the pistons...well they don't work either...



I hope someone gets a chuckle to start their day...



TOB