generators? are they easily overhauled??

[ob1]

or should I be looking round for a replacement

am thinking mine's packed it in - off a 1968 minimatic

is it worth trusting a local autosparky to do the brushes etc, or bite the bullet and get something else?

[shoutforjoy]

I assume that you have what we call in the UK a dynamo, rather than an alternator. Not that it really matters much, though some folks do like to upgrade to an alternator.

Here the cost of a new (or reconditioned) dynamo/alternator, between about £50 and £75, means that it is generally more cost effective to replace than repair.

I guess it depends on the availability of spares and/or replacement units in Oz.

[ob1]

thanks for that - yes it is the dynamo/generator

I'd like to keep as much of the original bits as I can, so will suss out first if they can do it and then how much! dunno if I want to to upgrade to the alternator unless they are more reliable and far cheaper, I'll keep an eye out for a replacement just in case - there's a place up over the mountain called the Mini King that I'll be checking out again thru the week then to keep my options open

cheers

[kalkat]

It is easy to replace the dynamo brushes. You will often find people selling brushes on e-bay


Emma

[notamini]

Creful to look and see if your Mini is still Positive Earth! The dynamo was usually found in that configuration. There is a quick and painless way to change it over to negative. Go herewww.mgexperience.net/article/neg-convert.html

That being said, there is an extensive section in the Mini manual covering the dynamo. Do you have a manual? I have one that is in PDF. Because it is 56Mb and not email-able, I can send it to you for download thru wetransfer.com

[jockduck]

Ahh! the venerable Lucas C40 used by the millions. When OTTOs dynamo was working poorly I checked it out and found that the commutator(bit the brushes run on) had been so machined in the past that it was under the recommended minimum size. I bought a new/rebuilt ?? for around $100 Aus and felt it was a good buy, that side of the cars electrics have been good ever since, the car is very standard and is only used once or twice a week for local runs. I have owned minis with alternators and the output is better than dynamos if your car had heavy use and has power sapping extras then an alt is a good move.
Jock

[ob1]

yep Jockduck, that's the one and that it seems is my problem - the autosparky said it would be cheaper for me to find another than to overhaul mine as the same thing (commutator?!) was so worn

for now she's in the garage with a battery charger on, but am keeping my eyes peeled for a replacement, and yes the mini is positive earth - I've seen a few neg earth ones on the net that they say can be changed, but dunno if I want the hassle unless I can't find the right one

[jockduck]

Changing from positive to neg earth is very easy from memory, some dynamos did it all by themselves without being asked. Dynamos rely on a thing called "reminant magnetisim" to get them started up in the right electrical direction, the soft iron of the poles remain magnetic when the dynamo is stopped, and when restarted this magetism begins the electrical generation in the correct polarity. This magnetisim can be reversed with nothing more sophisicated as holding the cut out points together for a couple of seconds with the engine stopped. This is real old school auto electrics I suspect some young auto electricians have never head of it. Basically you are circulating current through the dynamo in the correct direction to magnitise the poles the correct polarity. When you start the engine use an ampmeter to prove that the current to the battery is flowing the correct way, if its wrong the discharge will increase dramaticaly when the engine is reved! stop the engine immediatly if this is the case.
I had no problem getting my new dynamo through my local mini parts supplier. probably you only need an armature and you could even install one from another dynamo in yours and not have the polarity change hassle.
Jock

[notamini]

This website for Austin Americas helps quite a bit with the dynamo and polarity. Scroll down to the bottm for polarity.
members.tripod.com/austin_america/id64.html