Ford Autolite 25AMP generator

Gunfreak25 · Post by **Gunfreak25** » Sat Aug 20, 2011 5:31 am

The 24V Autolite generator used on my GMC M211 only makes power when turned counterclockwise as viewed from the drivers seat. It makes zero power when turning clockwise. Trouble is, the new diesel I am putting in turns clockwise, meaning It won't make power.

Why is this? Can it be repolarized to generate power turning clockwise? Are they directional? Do the brushes get worn in one direction? Is it broken?

Oldsalt · Post by **Oldsalt** » Sat Aug 20, 2011 7:55 pm

I think it would generate power in reverse polarity when it spins backwards. The regulator would not work correctly in that case so it would not generate at all. I believe you are going to have to swap the armature leads inside the generator to make it generate power correctly. It is certainly possible that the brushes take a set in one direction but I don't think that would stop it from generating. It might cause sparking on the commutator though.

Gunfreak25 · Post by **Gunfreak25** » Sat Aug 20, 2011 8:38 pm

Thanks, I may just sell the generator/regulator/cable instead. Since I no longer have a use for it. I found bolt on 24V alternators for under $100 that will fit the 6.2 along with a host of other motors. I had no idea alternators were so standardized.

Post by **wesk** » Sat Aug 20, 2011 8:41 pm

Since your 211 is loosing it's originality with the swap from gas GMC 6 to diesel why not just install a serious power producing alternator? If you want the military look use the 60 amp alternator kit for the later deuces. The old 25 amp system will be overtasked keeping up with the two heavier batteries you'll be using with the diesel.

Normally generators reverse current flow thru the fields to reverse rotation. The armature brush orientation doesn't change. Even if you reversed it's rotation the Group 4 shows no 25 amp opposite rotating regulators.

Gunfreak25 · Post by **Gunfreak25** » Sat Aug 20, 2011 9:04 pm

I will be searching for a good high amp alternator in 24V. Not because of the motor size (which is quite small) or battery size, but because I would like to add other 24V accessories to the truck later that would certainly max out any 25 amp system. Yuma being the hottest city in the USA I would like to pickup a 24V in cab AC unit which draws a lot of juice.

Don't get me wrong. If I had my choice i'd have the original 302/Hydramatic back. The previous owners did the first repower job, a junkyard swap using a 455 Olds. I am keeping the Th400 that came with it since it's already modded to fit the GMC tcase, but I am going with the 6.2 for economy and the ability to run veggie oil mixes. Couple more months and the entire truck will look like it rolled off the assembly line. It has fresh paint, upholstery, fixed all the body damage, cleaned every square inch and I polished every copper air line in sight. I am a stickler for perfection.