6V Charging issues..

[FLOPGUY]

I know, another thread.. but I am truly stumped.

I have read all the threads in here and used the diagnostic flow charts..

History: My charging system was not working, and when I bought the cub it had the battery backwards (neg ground).

What I did: I rebuilt generator (new bearings and Brushes), new Regulator, new amp meter and all new wires and wired it to match the diagrams and the battery is now positive grounded

What I suspect: it is charging backwards (if thats possible) is it possible I reversed wires in the generator?

Tests I have done:

1. removed belt and jump the terminal on the starter to the Arm terminal on the Generator and spun it like an electric motor.
2. polarized gen by touching starter terminal to 'A' term
3. 6.3v at battery with engine off. with engine running I only need to touch on battery with the neg lead and the numbers go wild..
4. with engine off and turning lights on amp meter showed neg draw.

Today I did what I call a "hot polarization" that is polarizing with the engine running and as soon as i touched the "A" term the amp meter spiked drain on amp meter. I shut it off immediately. I restarted and now it pegs negative every time and the my meter on the testing the battery is wild -1.238451 with the numbers tumbling. The amp meter was starting to get hot so I shut it down. I think I have some short at the amp meter almost like when the engine is on it is sending pos to one side and neg to the other..

Any ideas? I have looked at my wiring 100 times and it looks right.

[SONNY]

When you changed the tractor back to POS. ground,---Did you also change the wires on the amp meter?--Gotta do that when changing from one ground to the other, or so I am told!

[Glen]

Hi,
The Cub owner's manual says to polarize the system after connecting the system's wires and cables, before starting the engine.
Below is a page from the 1955 Cub owner's manual. The info begins at the lower left of the page.

http://farmallcub.com/rudi_cub/www.clea ... age-40.jpg

The people on here have said that a voltmeter with a dial and pointer works better for a Cub, not a voltmeter with a digital readout.

If what you said ruined the ammeter, you will need another ammeter.

If it doesn't begin charging when the engine is running, and you speed it up enough to where it would begin charging, the points in the regulator are not closing that turn the system on and off.
They close and turn the charging system on when you speed up the engine, then open and turn the system off, when you stop the engine.
The people on here have said that some new voltage regulators don't work right. You could have got one of those, I don't know.
The wires inside the generator have to be connected right too.

[FLOPGUY]

When you changed the tractor back to POS. ground,---Did you also change the wires on the amp meter?--Gotta do that when changing from one ground to the other, or so I am told!

I don't think the prior owner ever had it running, I think he put the battery in backwards... I did rewire everything to the schematics

[FLOPGUY]

Hi,
The Cub owner's manual says to polarize the system after connecting the system's wires and cables, before starting the engine.

I did polarize it with engine off many times to no avail, the amp meter showed a slight drain when running.

I did run the engine at 3/4 throttle while testing.

It was when I hot polarized when the amp meter went full drain and started to get hot.

Amp meter I feel is connected correctly, but pretty sure it is fried now..

I am beginning to wonder if somehow the amp meter is grounding out, because it seems to me it almost seems like the amp meter was hooked up to positive and negative..


Interesting about using a dial meter.. I never saw anything like this. my digital meter just needed to touch the neg bat terminal (while running) for the meter to freak out. The red lead just held in the air..

[tst]

one of the 1st questions on the flow chart is does the amp meter work, do you have lights on the tractor? if so it should read discharge when they are turned on, that will tell you the amp meter is working or not

[FLOPGUY]

one of the 1st questions on the flow chart is does the amp meter work, do you have lights on the tractor? if so it should read discharge when they are turned on, that will tell you the amp meter is working or not

Yes neg draw

[tst]

run a wire to the field terminal to battery ground post while its running and see if it charges

[Glen]

Hi,
If you polarized the system once, with the engine off, that is all the polarizing it needs.
Don't polarize it with the engine running.
Then running the engine the first time after that, if it didn't charge, something else was wrong, the generator, the new regulator, or the wiring.
Using the flow chart should have showed the problem.

[FLOPGUY]

Hi,
If you polarized the system once, with the engine off, that is all the polarizing it needs.
Don't polarize it with the engine running.
Then running the engine the first time after that, if it didn't charge, something else was wrong, the generator, the new regulator, or the wiring.
Using the flow chart should have showed the problem.

I have an IH ammeter on order, I had one that I bought at TS that the terminals for the wires ran thru the hold down using insulators. I think when I hot polarized I started it generating that shorted out thru the ammeter.

I realize what you are saying about polarizing with the engine off and I did that numerous times over the last 6 months to what seems like no avail. I am pretty confident with the wiring, I followed the diagram in my manual (which matches what posted here) and ran all new wires. I did the hot polarization as a last attempt.

Next week when I get my ammeter I will try again, I think my weak link is the ammeter.

[Glen]

Hi,
You didn't say what year the Cub is. Good if we could know what year it is.

TM Tractor has new ammeters they say are made in the USA and look like the originals. You can look at the pics. The styles of them changed through the years. There are 3 styles there.

http://www.tmtractor.com/new/el/el_001newparts.htm

[FLOPGUY]

Hi,
You didn't say what year the Cub is. Good if we could know what year it is.

Its bastardized between 48 to 52..

I put my new IH ammeter to no avail. as soon as it starts it pegs full draw.. I checked the wiring again and its right to the diagram.

My new thoughts are maybe I assembled the generator wrong when I rebuilt it.. perhaps crossed the wires on the brushes. I ohmed across the 2 terminal (disconnected of course) and as I turned the generator slightly the ohm meter jumped back and forth. Next step is to check that. when I rebuilt it I ohmed everything looking for shorts and breaks in continuity etc.

Does anyone have a wiring diagram for the generator itself ?

[Glen]

Hi,
It sounds like the wires inside the generator might be connected backwards, I saw one once that did the same thing you are saying.
Jim B had a drawing, I think, of the wire routing in the gen.

[FLOPGUY]

@ Glenn..
I have given up.. I am just going to 12v..
I redid the generator again and it worked a bit then the regulator started acting up and I checked the voltage at the generation and it was climbing until I killed it at 20v.. I need a regulator again... could even have a short inside the generator, wiring is very old.. no way.. 12v here I come...

[NJ Farmer]

I can only make this suggestion because it has happened to me. We “modern” mechanics really don’t ever deal with this problem on normal vehicles but since our tractor are made back in the 40’s and 50’s we all have forgotten one little maintenance item they ALL did back in the day and that was to “dress the points”!

The contacts within the voltage regulator get “burned” and sometime very badly and may become pitted. These points must be dressed with a very small flat file to allow for contact to continue the electrical flow of energy. The same principle as the ignition points in the distributor however “we” as mechanics normally just replace the ignition points and throw them away.

This problem happened on my 53’ 6 volt Delco Regulator and I opened it up an loosed the contacts and file (gently) the points and removed the pitting that was not allowing the points to close. My generator system is working Perfectly! Also I might suggest is that the voltage regulator has a GOOD ground from the voltage regulator bonding wire and the base of the voltage regulator.

I wish you success and hope you don’t convert over to 12volts because you really don’t have too.

NJ Farmer