8N Side Mount, Positive Ground 6V. Tractor

Its been a long journey, but the end maybe in sight. Started off with neighbor's 51 8N, overheating, stalling and antifreeze
leaking from tractor. At first I thought it was the lower hose, but it was the water pump. Replaced that for him with new pump
and now generator bracket would not line up with support on pump. Got that aligned after removing generator and bending the
support on the generator holding bracket. Still no start. Traced wiring and determined wire to ammeter had a partial short to
ground. Plastic bracket holding ammeter was melted causing high resistance ground between meter and frayed wire. Replace ammeter
and wire. Still no start. Found terminals at terminal block were dirty and needed to be cleaned. Tractor now started fine, but
exhaust pipe at manifold was loose and leaking. Needed to be properly positioned and tightened. Tractor now would no longer
start. Found battery to be low and needed to be charged. After charging, tractor starts right up. Checked battery voltage and
found voltage to be the same with tractor running and not running. Polarized generator by running a jumper wire from negative
battery terminal to armature stud on generator but see no increase in voltage with tractor running at mid to high throttle.

Question: If generator is polarized but still won't charge battery, what is the next step to take???? Is there some test I can
perform or will generator need to be taken to a shop for repair?

As always, thanks for any insight, suggestions, or help.

With engine running, jumper BATT to ARM just as you did for polarizing AND jumper FIELD to Ground and observe ammeter as well as battery voltage for signs of charging, If charging, then VR is the problem & generator fine.

In Jmor's test, you are bypassing the regulator cutout and field control.

You are providing full field.

moving the throttle / rpm from low to high should make the charge indicator go from low to high.

If you have or can get the FO-4 service manual there is a very good section on troubleshooting the charging system. If not then you may be better served to take it to a repair shop and have it tested. The regulator may be your problem, but I would not buy one until you have the generator checked out.

Did not see the post by JMOR, which is spot on.

Thank you guys! My neighbor is 86 years old and just uses his tractor to cut a couple of acres of grass ( when I don't get a chance to get my tractor out and do it for him) He relies on me to keep it running and I must say this has been a real challenge trouble shooting what started out being a rather simple repair (water pump) and then several intermittent problems. Really appreciate all who responded to my post.

Will this test work for a 12V system as well? I have a MF35 12V system that causes the battery to leak fluid. Don't mean to hijack thread but was wondering if regulator was allowing too much charge.

(quoted from post at 12:28:03 08/04/15) Will this test work for a 12V system as well? I have a MF35 12V system that causes the battery to leak fluid. Don't mean to hijack thread but was wondering if regulator was allowing too much charge.

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o, Bob, this is to determine whether generator is putting out or not, whereas your situation indicated that it is putting out......too much & overcharging battery. Sounds like a VR problem. Measure voltage across battery terminals after running it hard for half hour or so.