Morris Minor Owners Club

Hi team, got a problem with my altenator. when engines off ignitions light on dash on even without keys in. its also burning up and making a lovely winey noise and burning plasticy smell. i'm guessing that its kaput any ideas?

Hmmm - disconnect the battery quick! Is this a new alternator that has just been fitted - or an old friend that has suddenly gone wonky?
Not a normal happening with an alternator - sure it's not a dynamo ??

its about a year old. i've pulled the connecter out of it for now and stopped the draining of the battery. its deffently an alternator. i may off disconnected the battery when she was running think i may have killed the altenator can you get them reconditioned?

Well - they don't like running with no battery connected. Yes - I'm sure Hellfrauds and others will do an exchange service. May be cheaper/easier to pick one up from a scrappy. I refuse to pay more than £1 for an alternator at autojumbles. Always a good idea to have spare or two!!

Who did the wiring conversion for the Alternator?
First thing to do would be to check it is done correctly.
After that, replace the alternator and wait for it to fail agin (they can fail often on Minors) or change back to a Dynamo.

i did it myself and its been working fine for a year or so. i've got a radio fitted so probably need alternator. what's the best car to get similar one off at the scrappy?

i've got a radio fitted so probably need alternator

You don't need an alternator to run a radio - a dynamo will be fine.

o ok, can you run a dynamo with a negative earth?

Yes, but it will need to have the polarity changed if this hasn't been done already. See here for how to do this:
http://www.morrisminoroc.co.uk/index.php?page=322

mogatron wrote:o ok, can you run a dynamo with a negative earth?

Don't forget to switch all the other wiring back again - You'll need to bring the regulator back into the circuit....

so what's the general view on the alternator/dynamo position? also dynamo... black or engine green? cleaning the spare one up now

Green dynamo (the cast end plates should be unpainted)

i would keep your alternator..

radio / lights / windscreen wipers all going at the same time flattened my battery even when driving down the motor way with a dynamo.. i changed over to a alternator and have had no problems since.

Personally I've never had any problems with running lights, radio and windscreen wipers using a dynamo in any of my Minors but see this thread for some opinions on dynamo v alternator: http://www.morrisminoroc.co.uk/index.ph ... ic&t=27064

As your alternator is not working but you have a spare dynamo I'd fit that so at least your car will be back on the road. If you find that you get the same problem as Charlie Morris Minor refit the alternator but providing you are not driving for long periods with your electrics under load then a dynamo will be fine.

Alternators are deadly reliable in my experience - yes - even the £1 ones! I buy them - fit them - if they work I leave them on the car, until I buy another. It's a load of re-wiring to swap back to a dynamo. But in general I agree - if you have a working dynamo on the car, it's not worth changing to an alternator unless planning huge power zapping accessories. A 'wireless' takes less than 1 amp - so that doesn't count!

Alternators vs dynamos - depends on what driving you're doing and when. My current commute (45 minutes, mostly motorway) would be quite dynamo friendly. My old commute (hour, lots of sitting in slow moving traffic in the dark / rain) was extremely dynamo unfriendly - it struggled to keep the battery charged, and I'd fairly often end up resorting to starting on the handle. Which was less than fun in winter.

Dynamos, if you're doing that latter sort of commute really need to be in tip-top condition, mine probably wasn't, but rather than repair it I opted for an alternator. I had the standard minor conversion ones, quite a few of them, which repeatedly failed. I then changed over to a later mini alternator; more powerful and way more reliable...

IME Dynamos last essentially forever, Alternators can be troublesome, but if you're doing the kind of driving where you're sat at idle for ages in winter (fan/lights/wipers on) then you probably want the alternator.

Alternators charge at lower revs than dynamos which is why they perform better in traffic.

However they are a bit more delicate especially the diodes.
If you are going to arc or mig weld the car they need to be disconnected.
To be on the safe side they shouldn't be turned when disconnected so plug it back in before you start the engine.

Dynamos rarely need anything more than new brushes to bring them back from the dead.

cool, my commute is only half hour to an hour but i do got on lots of long runs too. think i might go get a new alternator tomorrow ish after grand prix. so do we recon a late mini ones the one to go for?

radio / lights / windscreen wipers all going at the same time flattened my battery even when driving down the motor way with a dynamo..

Something faulty there then. Would not happen without a fault in the system.

If you spend a lot of time in traffic, in witer with lights and wipers and heater on, and also short journeys - then it's worth to stick the charger on the car overnight once or twice over winter. This takes less time and effort than a conversion.

Alternators can be fairly reliable, however as of last week I'm now at double figures for failed alternators, but only had 1 dynamo go on me (fixed by replacing the brush spring). Had 16 Minors with dynamos and a few with alternators (most of which failed)

you've had 16 minors! now thats commitment.