gererator questions

Tue Jun 02, 2009 9:09 am

Ok
This is a little more then just a Farmall A generator. I posted about this over a year ago and I can locate the post in the forumn.
I am using an old Chrysler Corparation 6 volt generator/hydraulic pump all in one unit.
It was used for hydraulic convertable tops. I took it off a doodle bug tractor.
My question is the generator does not have markings on it for the Feild or the Arm.
How do you know which one is which? can you look down at it with the pulley up and the arm be the one on the left and the feild on the right? The one post is bigger then the other does that tell me anything?
any help with finding out which one is which would be nice. I want to wire this in using a voltage regulator by-passing the high low on the 4 way switch but yet still use that for the lights would anyone know how to tell me to wire this up?
Thanks
Chad

Re: gererator questions

Tue Jun 02, 2009 9:33 am

The large post should be the armature.

Re: gererator questions

Tue Jun 02, 2009 9:40 am

Thanks Big Dog
If that is true if I take my volt meter to the Arm to Ground will that show me the charging volts coming out of the genny?

Re: gererator questions

Tue Jun 02, 2009 11:43 am

Yes

Re: gererator questions

Tue Jun 02, 2009 8:30 pm

well I took a voltage reading at the battery before starting it was 6.31volts. I then took the positive wire of my meter to the arm on the gen and the negative to ground and at half throtal I got .31 volts and at full throtal I got .45 volts. I think the generator is shot.
I almost have to find a way to rebuild it since the Hyd. pump bolts on the end of it. any suggestions?
Chad

Re: gererator questions

Tue Jun 02, 2009 8:53 pm

Did you polarize the generator first?

Re: gererator questions

Tue Jun 02, 2009 9:21 pm

I think the generator is shot. I almost have to find a way to rebuild it since the Hyd. pump bolts on the end of it. any suggestions?
Couple of choices. Take it to an automotive electrical repair shop. Take it apart and see what you need to repair, replace. Bearings and brushes should be readily available. Big problem will be the commutator - if it needs to be turned and undercut.

Re: gererator questions

Wed Jun 03, 2009 5:16 am

Big dog
I am just trying to take readings with the volt meter I am not sure the wiring is hooked up right so I didn't bother polarizing it using the voltage reg jumping the bat to the gen.
Can you just polarize the generator by itself?

Eugene.
The bearings all seem good it spins very easy no noise so I am guessing the brushes? Should the brush pull away when you pull back on the spring loaded retainer?

Re: gererator questions

Wed Jun 03, 2009 6:54 am

Chad - polarize by applying battery voltage from the generator case (ground) and the A (armature) terminal on the generator.
On the brushes - yes, if you pull the holder clip back the brush should slide in the brush holder. Pull the brush out and see how much brush length you have left. The contact surface of the brush should give you some idea of what the commutator looks like. If it is smooth the commutator is probably in good shape. If the brush is grooved, so is the commutator.

Re: gererator questions

Wed Jun 03, 2009 8:26 am

cjpenny89 wrote:I then took the positive wire of my meter to the arm on the gen and the negative to ground and at half throtal I got .31 volts and at full throtal I got .45 volts. I think the generator is shot.

Ground the generator F terminal when you do this test.

Re: gererator questions

Wed Jun 03, 2009 8:38 am

Bigdog wrote:Chad - polarize by applying battery voltage from the generator case (ground) and the A (armature) terminal on the generator.
Darrell, are you sure you typed that correctly?

Re: gererator questions

Wed Jun 03, 2009 8:53 am

Well - now that I re-read it - no............ need another cup of coffee...

Re: gererator questions

Wed Jun 03, 2009 9:17 am

Jim
I took the same readings with the F grounded and I do not think it got better possibly worse I will re check it tonight.
Chad

Re: gererator questions

Thu Jun 04, 2009 9:01 pm

Jim
I don't know how this can work but I did the test with the feild on the gen grounded and checked the arm with the volt meter and it read 32 volts. un-hooked ground from feild and tested and it reads about .4 volts on high throtal.
What does this mean?

Re: gererator questions

Thu Jun 04, 2009 9:09 pm

Sounds like the generator is OK.