Circa 1958 Emeraude C90 generator no longer charging

[MEL_GALE]

I suspect the generator and regulator box are original as there are no entries in the legacy engine logs to suggest them ever having been replaced.
With the engine running the volt meter is only reading 10V. Any suggestions as to where to start looking for the problem, could it be generator brushes? are they still available for an old C90 engine generator? regulator boxes are black magic as far as I am concerned, but I seem to remember it being a problem with my Austin Cambridge back in 19 hundred and frozen to death era.
Any logical progression of fault finding will be much appreciated, as well as any information on where to obtain spare parts should they be required.

[iancallier]

Forget any UK (make their own parts). return it to USA for overhaul. Well: order the overhauled item, keep your drive - then return your old as a core.

[Peter Thompson]

I think that the brushes are (or were) available under Cessna Part No. 1906984. I bought some from Multiflight at Leeds/Bradford, although that was a few years ago.

[MEL_GALE]

Thankyou for your input. I think first line of attack will be the brushes if I can source them.

[Rob Swain]

Last time I needed a dynamo fixed I took it to an auto electrical overhaul place.
They stripped, cleaned, checked (and fixed) continuity of all coils (fixed and rotating), cleaned and lubed bearings/bushes, turned the commutator in a lathe to put a nice new smooth finish on it, oh yes, and replaced the brushes and springs.
Didn't need painting as was in reasonable nick, but they would have done that too.

They tested it too, off the plane, so there's not the aggro of putting it back on just to have to remove it again if there is an issue.

Think it came to around £100, although that was around 8-9 years ago.
Might sound like overkill, but if it dates from 1958 I think we can say it's probably due an overhaul.
I would consider a competent auto-electrician overhaul as fit-for-purpose for a Permit aircraft.
Probably be OK for a CofA one too, but I'm not advocating that!

They also sorted the old buzzy type regulator (like your old Cambridge had), but hindsight says I'd ditch that and buy a Zeftronics solid state regulator.