Farmall 656D not charging, diagnosing Delco Remy generator and regulator

Trying to sort out some charing issues on my Farmall 656 Diesel, it's an early model (1965) with a generator, does have the single battery and standard 12v Neg ground system. So far I have taken the generator apart, cleaned the commutator and brushes (looked fine). Generator is working fine, when you ground the field wire it charges at 13-14v. I've also cleaned all the connections, grounds, etc. Have continuity on all wires from the generator to the regulator, to the tellite, and tractor harness. Tellite works and thinks the system is working but it isn't, light will be on with key on engine off, start the tractor and the light goes out as it should, but no charging. After all that I figured the regulator must be bad, installed a new one from NAPA, Echlin brand made in USA, polarized it as per instructions and still nothing. Possibly bad unit out of the box? It's such a simple system, not sure what else I'm missing?

Are you measuring voltage at idle? Many of those old systems will not raise the voltage to the batteries until you apply some rpm.

mg2361 said: Are you measuring voltage at idle? Many of those old systems will not raise the voltage to the batteries until you apply some rpm. Click to expand... Yes and at higher rpm as well. This system normally will run 13-13.5v at idle when its charging, for a generator it actually works pretty well. I thought I was going crazy not being able to figure out such a simple system, but it turned out the new regulator I bought was DOA. I know the overseas ones are pretty hit or miss but I thought the USA made NAPA unit would be good, must have just gotten a bad one. I know most people would just slap a 1-wire alternator on it and call it good, but this is a very original tractor and I'd like to keep it that way if possible. Will see how long this new regulator lasts, crappy replacement parts seem to be the downfall of all old equipment.

The mechanical voltage regulators now days are junk. It's charging now but keep your fingers crossed, it might not last long. That is what is very frustrating about aftermarket and parts for older equipment. Sometimes you have to fix the parts before you can fix the machine.

I don't mean to hijack your thread..... I'm curious what can actually go bad on a regulator? Do the springs get weak? There just doesn't seem like there is much to them yet I hear about them going bad quite often.

bam1968 said: I'm curious what can actually go bad on a regulator? Click to expand... Many old voltage regulators are just relays under that steel cover. One relay for the low voltage setting, one for the high voltage setting and one for current regulation. Like any other relay, the point contacts can go bad or the fine wire in the relay coil can fail.

Yes, that's exactly what theses regulators are like. I'm guessing the new ones that don't work are either improperly adjusted or bad connections from the factory. They probably also fail quicker for the same reason we can't buy a decent set of points anymore, cheaply manufactured with poor quality materials.

NAPA and Standard/Silver Streak points and condensers are still good quality. You'll pay $50.00 for a set of points and condenser though.

Before you guys get done ranking aftermarket ignition/charging components made today, It wasn't much better years ago. I went from when started mag/coil/point ignition/ to the latest coil-pack. Back in the 50's/60's/70's life expectancy of ignition coils & condensers was a roll of the dice. I liked setting ignition timing with a test light, it was very accurate. We use to tweak the contacts in regulators to allow higher charge rates.

Use that hacksaw blade on a bench armature {growler test}.