Hi VP, I started on rewiring the 60 year lighting plant today. The cloth covered rubber insulation on the wires has perished and they all need to be replaced. I am hoping your new generator head is in better condition but if not I am hoping that my approach to this will help you.
First thing to understand is that this unit has four sets of coil windings one set for north/south pole for generation and a second set for turning the generator into a starter motor. The set I have been playing with today is the starter motor windings. They are solid copper windings with a cloth insulation. When these were made the cloth would have been in perfect condition, they would have wound the coil around a former and then soldered on the external wires as needed. The coil would then have been tied up tight, with cloth, before the whole thing was immersed in varnish. Back in the 1950`s this would probably have been a shellac based varnish.
This process ensured good insulation between the coil and also fixed them in place to ensure no movement or chafing between the layers, under load. So what can we do to restore them without having to send them for an expensive rewind? The first thing is to check the resistance between each end of the coil. We do not want to see either 0 ohms or infinity ohms, in between is good.
The second job is to very carefully remove the cloth covering that holds the coil together, this will give access to the soldered connections between the solid copper core and the more flexible interconnection wires. Now cut out the damaged wires and replace them using crimp connectors with the plastic covering removed. (be sure to clean the wires before trying to solder them) Crimp them tight and then solder them in place, now cover the joint with heat shrink, I like to use two layers of heat shrink
The next job is to put some surgical tape around any part of the coil that has movement in it, now immerse the entire coil assembly in polyurethane varnish, let it soak right in before removing and allowing to dry, brush off any excess varnish to avoid drips/runs and etc. Leave to dry.
Next is to wrap the coil to make sure it cannot come apart. I have tried all sorts of insulation and cloth tapes and have found that Micropore surgical tape is second to none; it is cheap, strong, porous, self adhesive and readily available but most important of all the adhesive does not dissolve in polyurethane varnish. Once you have wrapped your coil with Micropore tape it`s back for another swim in varnish, pull it out, brush off any drips or runs and let it dry for a day or two.
When done it should look something like the photos below.
Bob