Farmall 706 charging problem

I have a 1967 Farmall 706. It has the german diesel engine. I have been fighting a charging problem the last couple of months. I have had the battries checked and one was bad so I replaced it, I put a new voltage regulator on it, and I had the alternator tested and it"s output was a little low so I replaced it. The only thing I have not replaced is the resistor, but it seemed fine. Is it normal for the alternator light to be on at idle? I do not remember it being on before. If not does anybody have any other suggestions on how to fix the problem.

Thanks,
Tjh72

If you're not a really, really old guy like me, that system is kinda hard to diagnose. :>)

Tractors use a bigger pulley than autos to make 'em turn slower/last longer. In so doing tho, everything has to be right up to snuff to make it work "normal".

Did you adjust the regulator after you put it on? Did you put a voltmeter across the system to read the actual voltage? Will the system (voltage) pick up the load of the field lights? Are the batteries charged up good? Alternator belt good and tight?

"Usually" on that system, if the light comes on at low speed, it indicates that the alternator is only working on two legs and it is struggling just to "maintain".

Put a voltmeter across the battery(ies). It should read somewhere in the neighborhood of 14.5 volts after the system has stabilized from starting. Pull the field lights on.

The voltmeter should drop a volt or two for just a second and then come right back up to the 14.5 volts. If it doesn't, I'd really suspect that new alternator.

ALl that resistor does is bleed off a certain amount of differential current thru the bulb under hard charge to prevent a "dim" bulb showing up at night.

Allan

On my 706 when I start it at slow idle the red light will come on. It will stay on unless I throttle it up maybe 1/3 throttle then it will go off. After that initial time I can slow tractor way down and it will not come on.