Sidevalve dynamo?

[DAVIDMCCULLOUGH]

Having assumed that my charging problems were due to a knackered regulator and having fitted a new one, its still not charging....

Is the sidevalve dynamo the same as a later one? Mine has the fan blades fitted to the front of the dynamo, does this just screw off to fit another dynamo?

[mike.perry]

The Series MM uses a C39PV dynamo with a screw terminal regulator, later cars use a higher output C40 dynamo with a spade terminal regulator.
The fan blades and pulley assembly should unbolt from the dynamo shaft. See fan blades topic
Slide the inspection cover back and check the dynamo brushes, they probably need replacing. Note C39 and C40 brushes are different sizes

[DAVIDMCCULLOUGH]

The fan and pulley came off ok after putting a rope round it and tightening it in the vice to hold it in place to undo the bolt. I have ordered a rebuilt c39 from Classic + Vintage Dynamoes in Nottingham who were the most competitive, so hopefully it will be here on Monday.

[DAVIDMCCULLOUGH]

I fitted the new dynamo, still not charging..... I didnt know what else to try so took it to a friend who's good with electrics. He checked all the wiring with a meter and reckoned there was no reason for it not to charge. It turned out the new regulator points were dirty, so after a good clean the it started to charge!

The MM had been going really, really badly the last time I drove it, I replaced the condensor with an old one and it went a bit better. While I was getting the wiring checked Robert looked at the timing and found it to be way out and wondered how it was going at all. It felt like a different car when I was driving it home, much more accleration and more responsive requiring a lot less changing up and down through the gears to get anywere. It might use a bit less petrol now as well.