Morris Minor Owners Club

Whilst alternator off and in bit I've ordered the rectifier pack too.

Thanks again for all the advise

Nno wear at all on the end of the broken brush so no idea hows it been working!

Wes wrote: ↑Sat Apr 19, 2025 2:25 pmBingo

Hurray!

Wes wrote: ↑Sat Apr 19, 2025 2:39 pm Nno wear at all on the end of the broken brush so no idea hows it been working!

Very strange that it's broken like that, but without that braid you're just relying on the output going via the various contact surfaces of the brush moving in the holder; no wonder it's been giving problems.

It’s left me wondering why the warning light was illuminated while the ignition switch was off. Sorry, but I still think the rectifier is the culprit!

oliver90owner wrote: ↑Sat Apr 19, 2025 11:00 pm It’s left me wondering why the warning light was illuminated while the ignition switch was off. Sorry, but I still think the rectifier is the culprit!

It's one of those tales that leaves you wondering which bits of the story are being omitted in every post, with clues mentioned then not mentioned, etc, etc....
Flitting from one thing to another instead of methodical fault diagnosis.....
He's apparently ordered a rectifier pack, but no mention of checking it first...

Someone mentioned brushes I started with that. Found a fault, went to order brushes and saw that a kit incl the rectifier was only £18. So as a few comments on here about rectifiers being a culrpit it seemed like a no brainer buy the two. Sorry if i didn't venture into the realms of electrical diagnostics that i'm not comfortable with. I'm more in the camp of throw some money at it and just get back to driving it.

OK brushes replaced, rectifier replaced, alternator refitted. All warning lights go out and stay out on start up

Thought I'd just check the voltage at the battery. 12.4V before start up, 14.2V on idle but rev the engine and it peaks at 17.4V. Guessing this isnt good?

No, not good, sounds like a diode pack/rectifier problem.

all this is new!

So ive missed a Spring show and missed Drive it day. Should have done what i thought first and just buy a new alternator and get back to driving it

That’s a shame but a new alternator won’t help you if the wiring is wrong. Why don’t you get the alternator conversion mini wiring loom from ESM and install that as well as the new alternator (if you must get a new alternator). I would be checking all the wiring first.

Stephen

Happiness is a brand new working alternator delivering ~14V no matter what the revs

There were two alternatives - cheap dodgy parts or dodgy repair. Care to let us know?

No idea if the parts i received were dodgy Chinese ones or if my repair/soldering was substandard. So to get back on the road (annoyed i missed National Drive it Day faffing with the old alternator) I bought a brand new one from BBClassics. Job done.

Soldering? What soldering?

Repairing the brush wiring, if you care to look back !

oliver90owner wrote: ↑Thu May 01, 2025 8:35 am Soldering? What soldering?

Soldering the shiny plated thing(?) to the 3 wires from the windings and the two red wires

You soldered to the diodes? Why?

oliver90owner wrote: ↑Thu May 01, 2025 6:17 pm You soldered to the diodes? Why?

This photo was as it was off the car. I just copied this with the new parts. Why the long prongs on the new one then?