Fried wire on voltage regulator

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Jan 31, 2012
Just finished, so I thought, installing a new painless harness into my new-to-me 4/75 40 with a 2f. I checked the blower fan, turn signals, headlights and they all worked a off the low amp. battery charger. I then hooked up the battery, located all the fire extinguishers in the garage, turned the key, nothing happened. I then proceeded from the drivers seat to the hood and immediately notice smoke from the drivers side firewall. After closer inspection I found that the igniter wire on the voltage regulator was fried.

My question to you all is....what would cause this? And how do I determine the cause? And what would be the possible solutions?

Also, do I need to ground the new ground wire that I installed with the harness or will the ground from the alternator and switches be sufficient?

My 0.02 cents... If the IGN wire is fried, I think that wire is hooked up to the ground terminal instead of the IGN terminal of the Voltage Regulator. If that's so, why didn't the 15 Amp "engine" fuse blow?

Just thinking...

Have you checked the voltage regulator to see if it is wired correctly? I had my wires crossed on my when I rewired my rig. Didn't blow the fuse and it filled the engine compartment with some major smoke.
Thanks for the input. I will give this another try when I get the two new regulators next week. I ordered a backup.
Scouting cruiser,
When you smoked your VR did it even start. I didn't even get the starter crank and it was fried.
I don't think he smoked his VR. I think he smoked only the wire to the VR because he had that wire connected to the ground prong instead of the IGN prong. Fat chance that the VR is still alive.
My 0.02 cents.

Thanks for the info guys....Just installed the new voltage regulator and after sitting in dry dock for 8 months she fired up. While inset dock I repla
....Oops. while in dry dock I replaced the wire harness as the previous post mentions.
The question I have for you all is, why should my ammeter be pegging out +? Could it be a low battery? Or wires crossed?
FYI, I have a 60 amp maxi at the battery, and one right after the ammeter as well as two 15 amps at the voltage regulator, 1 on the exciter and one on the field wire as insurance.
Thanks for the assistance,
Should be around 0 when at idle.
When it's pegging out when you rev up the rpm's it's normal charge behavior. It will take 10 minutes or so before it comes back to half, quarter and almost zero if the battery is low.

After giving it some time and adjusting the idle the needle returned to just above neutral. I should have been more patient but I was concerned about smoking the VR again. Thanks for all your input it was great.
Okidoki, problem solved.
Glad to be of any help.
Did you figure out what made the igniter wire to smoke? Was it the regulator or a wiring error?

Happy :steer:

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