8N 6v Generator rebuild?

[Hammbone]

So I ran the tractor for a couple hours this afternoon pulling the box blade with rippers down to rework a washed out ditch. It was almost full throttle work for close to two hours, and afterwards, I noticed that the battery had been bubbling over. I turned the tractor back on, and at full throttle it's getting 8.3 volts at the battery!! Is that to far off to try adjusting the spring tension in the regulator, or would I be better off replacing it?

 

[Soundguy]

try this as a test.

take a few measurements.

tractor off, just starterd, idle.

idle after a few minutes,

mid throttle

full throttle.


if the votlage is 7 at idle and 8 at high then idle.. you may have a stuck field contact in the regulator.


alternately. if the ammeter goes positive at startup and follows throttle. ie. more throttle make more amperage.. and full throttle acts like 20+ amps, and it never tapers off.. then the field ont he gen is staying grounded.

as a test pull the field wire fromt he gen and see if charge drops off. if it does, make a temp wire from gen field to reg field and do not use the wire in the harness in case it is grounded.

post back.

 

[Hammbone]

I tried the test you instructed and here are the results:

Battery voltage pre start: 6.4v
Battery voltage after start at idle: 6.29v
After a few minutes at idle: 6.4v
Mid throttle: 8.7v
Full throttle: 9.02v
Pull the field wire and the voltage slowly begins to drop( assuming this is as the residual magnetism of the fields wears off?)
Then, running a temp wire from genny field to reg field , all results were nearly identicle to first test.

P.s. the amperage did follow throttle( more throttle more amperage). It also maxed out at 20+ amps even with three lights on after about 3/4 throttle.

 

[Soundguy]

as long as pulling the field wire makes it stop charging ( negative on amp meter.. etc.. ).. then the issue lies within the vreg feild circuit.

heck.. field contacts may even be welded together.

 

[Hammbone]

as long as pulling the field wire makes it stop charging ( negative on amp meter.. etc.. ).. then the issue lies within the vreg feild circuit.

heck.. field contacts may even be welded together.

I opened it up just before I got it charging.
I haven't opened the regulator since it started charging, but everything looked normal before, no burn marks, the contacts moved freely, and all soldered ends were intact( I'll have to open it up again for further investigation though and see if I can maybe increase spring tensions to bring it down some if it isn't fried.

 

[Hammbone]

Ok, couldn't take it. I went out and pulled the reg. out and brought inside. As soon as I opened the case a burnt smell came out good and strong, however I don't see what burned up. The normally closed points still open when pushed down, and the normally open points still close when pushed as well. Think I will be looking for a new vreg......

 

[Soundguy]

yup. could be some shorted turns on one of the 2 or 3 bobbins.

it's charging but high. you MIGHT be able to adjust it.. but then it might just keep on going too.