Adding a Charging System to an Unstyled D

Last week we gave you the story of two brothers who added electric start to an unstyled “D”. This week we follow up with the system they added to keep the batteries charged. 

Having converted our 1930 “D” to electric start, my brother and I decided that we needed a charging system. A check of the unstyled “D” parts catalog showed that a charging system was an option for “lights only” since electric start wasn’t available until later.

The key component to the system seemed to be the generator mounting bracket (PN D278), which bolts to the side of the governor housing. This was a pretty rare option, but we found that Sharp’s Old JD4U, of Fair Grove, Missouri, offered a reproduction bracket on its website. Donnie Sharp had restored an early “D” with this option a while back and while he had it apart, he had used the original bracket as a pattern to have a few examples recast. We ordered one (Photo 1).


Next, the rear facing generator needed to be found. A call to A.E.S. in Racine, Minnesota netted us the correct rebuilt Delco generator, wired for 12 volts, and the correct part number pulley for the end of it, along with a new regulator. Now, the search was on for the split belt pulley (part number AD2339R) that mounts onto the fan shaft to drive the generator. A check of Greg Stephen’s website showed that he had some in stock. An order was placed.

Donnie Sharp had warned us that the spliced, figure 8 V-belt could be a problem. We decided to try a perforated one from the McMaster-Carr catalog. It arrived in green!

We decided to go with a new white faced John Deere ammeter, mounted in a used housing from an Allis-Chalmers WD45, painted green! We think it looks pretty good (Photo 2).

After all the parts were assembled and the generator polarized, it was time for a test drive. About halfway across town, the generator quit charging and it was found that the spliced, figure 8 belt was broken. The split belt pulley had slid back on the fan shaft and stretched the fan belt until it broke at the splice. Back to the shop!

After removing the split pulley, all the paint was shined off the fan shaft, using a strip of emery cloth. Next, the screws that hold the split pulley halves together were replaced. Instead of the “screwdriver head” screws, we used new Allen head screws and snugged the pulley halves down much tighter on the unpainted shaft.

Luckily we had ordered enough belt material to make an extra belt. Now the pulley stays put and everything works nicely.

We are quite happy with this set-up and it makes for quite a conversation piece on our “D.” When we get a chance, head lights will top it all off. See you at the next show.

Submitted by,

Loren Skatter

Lake Mills, IA