Technical Article

C35 Starter Repair (for pre-war Lester P-Type)

(as appeared in the Jun, 2006 TSR)

By John Wright

For this issue’s technical topic I thought going over what I had to do to the ancient C35 Lucas starter and associated parts to get my Lester P-type to turn over better might be of interest.

Being a prewar unit, I was interested in finding out about a 4-brush modification to this relic. A message to the prewar MG Internet list brought a few comments. Very helpful was Barry Riseley from Tasmania, Australia. Barry suggested that the Lucas 35G starter on 12v should be more than capable of turning my engine around smartly and that I should check to make sure that all the things I would normally do for a weak starting system be preformed. Forget about the 4 brushes is basically what he was saying, so back to the basics. What I found were basic problems for sure and here is what I did and all would apply to our T-types. I changed the cable from the foot operated starter switch to the starter to a heavier #4 cable. Has someone changed the cable on your car to one not much larger in diameter than a pencil? Lots of current loss through one of these and we need everything we can get here. The cable from the rear-mounted battery up to the starter switch was fine so, next I removed and disassembled the starter for some clean up. The brushes were worn down, needing replacing. One was actually partially grounded. I did not have a set for this starter as they are the bronze/carbon type, but they are working for now after some adjustment. I polished the commutator with very fine crocus cloth with the armature chucked in my small lathe, not being necessary to undercut the insulation. The bushings were fine and the field coils passed the cursory visual look. Finally, the cleaning of the starter case and the surface of the bell housing where the starter bolts up may have been the most serious of the problems causing the slow turn over of this engine. The 2 surfaces were oil soaked, which will insulate the starter as it gets it’s ground through the engine ground cable. After giving the starter some real basic attention, I am pleased to say the starter does turn the engine over smartly. Fires right up, which is something it has not done in the 6 months I have owned this car.