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9 posts • Page 1 of 1
Ok guys, next problem.
The charging gauge shows a negative number and the battery doesn't appear to be charging.
I haven't gone through the wiring connections to see what the previous hack....I mean, owner rigged.
Just wondering if there is a "typical thing" that causes this issue.
It's a '47 with a rebuilt generator (supposedly), so it's 6V with a positive ground which is kind of odd for me.
Any where there is a wire connection, starting with the Field and Armature connections on the genny and work back toward the battery.
Get out your wire brush and wire brush every bolt/screw connection.
Then, if still not charging, I took the cover off the regulator and manually moved the contact levers while running and all was back to normal.
If there is a "typical thing" that goes wrong in a charging system, it is a lack of good ground connections. For a cut-out system (what your tractor had originally) to work, you need to have good grounds not only for the battery and generator but also the CUT-OUT and the HEADLIGHT SWITCH.
Don't take the cover off the cut-out (or regulator) until you have eliminatad all other possibilities. More regulators have been ruined by taking the cover off than have been fixed by taking the cover off.
6V positive ground was the standard in the 1940's and well into the 1950's. That's for tractors, cars, trucks, everything... 12V negative ground is something fairly new.
A quick test to see if the generator is okay: Connect the F terminal on the generator to the tractor's frame. If the generator starts charging there is something wrong with the cutout/regulator or the wiring or the ground.
I have a test lead with alligator clips on both ends for this kind of troubleshooting, though last week I used a piece of smooth fence wire to perform the test on my Dad's tractor.
GM vehicles have been negative ground as far back as my knowledge goes. I learned a lot about driving in a 1933 Chevrolet with most of the body removed. Had never driven on paved road until I was taking the driver license road test on my 16th birthday- passed. Never have seen a Chevrolet with positive ground.
Luck favors those who are prepared
I should have known.
I also have two 60's era VW Buses and whenever there is an electrical problem it's almost always a ground connection.
I will have to run the connections this weekend, assuming it's warm enough to do so.
Spring can't come soon enough this year.
So while I had the hydraulic cylinder out (see other post) I decided to debug the wiring.
Between two different diagrams I found on the site I was able to figure out the issue.
1. The PO had the light/charging switch wired incorrectly
2. The generator needed to be polarized
Charges nicely now!!
Nice to hear that the gremlin was found and fixed Sometimes it really is the simple stuff
9 posts • Page 1 of 1
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