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So the early works cars used an up rated dynamo with an RB40 control box, I can see the case is bigger than a mini C40, 4" case. But was it a C42 or a C45 4.5" case?

This is what's listed on EJBs build sheet

I see you can only get 28 amps by making the coils bigger or longer. The EJB listing as a C40 doesn't fit what is in the image.
Where are the works or electrical expert comments ....

This is a 22746 C40R

Thanks for the images Simon, that is one very rare part. All the dynamo specialists I've spoke to have never heard or seen a C40 R.
You would have thought it was adapted from some other Vehicle in the Bmc range. If anyone knows what a 22746D was used in ?.
Or I'm going to have to build a replica, I found that a C40L has a 28amp out put, but unsure of its dimensions.
The C40R in the above images has a band round it, a bit like a starter motor, what would this be for?

My mate Jeroen made one by shortening and welding up a larger Jaguar one. He also squeezed a modern Denso alternator in, unvisible from the outside:




If you're on facebook, check this album https://www.facebook.com/media/set/?van ... =-UC%2CP-R:

He spend 6 weeks to do the complete wiring on this CRX89B replica (1964 RAC version).

Cheers,
Ronald

Yes I've seen this..very impressive, looks very authentic from the out side.
I may do something similar with the case, but no modern internals

NZmember wrote: ↑Wed Sep 15, 2021 9:11 pm I see you can only get 28 amps by making the coils bigger or longer. The EJB listing as a C40 doesn't fit what is in the image.
Where are the works or electrical expert comments ....

that's exactly what I thought, C40=22 amps. That's why I assumed it must have used a bigger case .
Seeing as it was a 4" case used ..I think the fact it used bearings front and rear and an RB 340 control box, it could take the revs more meaning more Amps generated?

May have been from a lotus climax engine. The band was for changing the brushes. I think I might have found one.

I was told there was one used on early lotus engines that was similar. That was from a reconditioning specialist, he said he could replicate something similar for about £350 and that was about 10 years ago .
The ends are cast iron and have special heavy duty bearings I believe.

251 ENG wrote: ↑Thu Sep 16, 2021 1:22 pm I was told there was one used on early lotus engines that was similar. That was from a reconditioning specialist, he said he could replicate something similar for about £350 and that was about 10 years ago .
The ends are cast iron and have special heavy duty bearings I believe.

Sounds like this one Jim can make from classic&vintage dynamos

https://www.powerlite-units.com/dynalit ... sions.html
https://www.powerlite-units.com/dynalit ... ample.html
Seems to be available easily

Seems like Trevor and Dynalite have the answer if you want yours to look the same. If it's purely aesthetics, why go to the hassle of converting?

I stuck modern guts into mt crap 11(?)AC alternator to make it sort of look original.

Have fitted Dynalite Alternators on two cars & they have been no issue at all ..just needed small modification when fitting to make sure Belt Alignment was correct as one unit came with a different thickness front plate to water pump .. i had to exchange in the old dynamos..one was in bits but they just wanted the used outer case & end plates... would buy again.

Is that still a 4" case that Jim uses?

It's exchange so I guess it must be

Jim told me it's an old C39 case with recast end plates. No exchange needed on this particular one.

Copy that
It's good to know

could this be of help.

https://www.autoelectricsupplies.co.uk/product_list/165

Nick W wrote: ↑Thu Sep 16, 2021 2:03 pm

251 ENG wrote: ↑Thu Sep 16, 2021 1:22 pm I was told there was one used on early lotus engines that was similar. That was from a reconditioning specialist, he said he could replicate something similar for about £350 and that was about 10 years ago .
The ends are cast iron and have special heavy duty bearings I believe.

Sounds like this one Jim can make from classic&vintage dynamos

I guess this one takes some kind of pump/exhauster at the rear.