Returned from my friend's place moments ago. Worked on his '90, Ford 3930 tractor. His complaint was, after stopping the tractor to take a break yesterday, it wouldn't re-start. All he heard was a clicking sound, sometimes. He wasn't sure where to begin checking, so he called me last evening.
I drove over this morning and began diagnostics using my Fluke multimeter. After some checking, I found the problem to be a bad connection at the Positive battery clamp.

Below was the culprit.
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I tell people, this type battery clamp should only be used to get yourself out of a bind. It should not be for long-term use.

I installed a solder-on type clamp. He had no rosin-core solder, so he called his neighbor who brought some over. This clamp should last quite a while.
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This is a shot of his tractor. The tractor was purchased new in '90 by his dad. After his dad's passing, he inherited the tractor. This is the same guy I bought my 330 from. His dad was also the original owner of the 330.
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While I was there, I took a pic of this disk. It looks new. It was actually built in 1969. Last year, he completely disassembled it. He had the frame and gang supports blasted and painted. He then replace all bearings, blades, bolts(flats, locks and nuts) pins; and re-assembled it.
Check out the adjusters for the gang angle. I don't recall seeing too any disk harrows with a crank for the gang angle adjustment.
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