Morris Mini 1962 - Dynamo

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Mon 22 Nov 2010 13:39
Morris Mini 1962 - Dynamo - vince208
My car has been off the road for a while and I recently changed the car to negative earth, which only involved connecting a battery charger to the car in place of a battery and 'flashing' the dynamo. I disconnected the charger and thought no more about it.

At the wekend I connected the car up to a battery charger again to test the lights. When I connected it up, the needle on the charger went to max and a murmering sound started coming from the dynamo. The red light on the dash was bright even though the key was in the 'off' position. When I turned the key to 'on' the ignition light went out!

With the dynamo disconnected all else seems normal.

Does antyone have any idea what the problem could be, and is it connected to me 'flashing the dynamo? Despite lots of information on the web I wasn't sure how to 'flash' the dynamo. Should the car be connected to the battery charger with the ignition on, or off? Do you connect the big and small terminals together with both spade connectors in place, or removed?

It might be time for me to change over to an alternator, but I am reluctant to do so because the instructions for how to deal with the wires of the regulator are not clear. If anyone can help, I will let you know what my regulator wires are coded as.

Very grateful in anticipatiion of assistance.
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Mon 22 Nov 2010 14:17
Morris Mini 1962 - Dynamo - Avant

Moved to Technical, where I hope you'll get some advice - hopefully from someone who remembers the dynamo or who can advise on changing to an alternator.

It gives a nice nostalgic feeling to see 'Morris Mini'! My wife's first car was a Morris Mini-Traveller: the original Morrises were less susceptible then Austin Minis to water knocking out the ignition, as the radiator grille slats were closer together. Hers never had a problem.

Edited by Avant on 22/11/2010 at 14:18

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Mon 22 Nov 2010 14:37
Morris Mini 1962 - Dynamo - elekie&a/c doctor

To flash the dynamo,all that is needed once the car has been converted to neg earth,is to take a piece of wire and connect one end to a (now) positive supply,easy from starter solenoid,and just touch it to the small terminal of the dynamo a few times.Remove wire from this terminal first.You are probably better off with an alternator conversion as a dynamo on these only has an output of around 22 amps.Once the bracket arrangement for an alternator is fitted,then wiring is easy.You will need a new power supply cable from the alternator to the starter solenoid power terminal.The warning light wire can be retained by joining the original "F" terminal wire to the warning light wire at the dynamo regulator.Wires removed from reg.Leave the regulator in place.Doing this will give an immediate power increase to at least 35 amps.hth

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Mon 22 Nov 2010 14:41
Morris Mini 1962 - Dynamo - vince208
Thanks. Given that the starter solenoid is under the floor (push button floor start) I'd rather conectthe new alternator to a home inside the bay. Which wire is this on the regulator? And is the power supply the small wire spade or the large spade on the alternator? You mention joining the 'F' wire to the warning light wire. What letter code does the warning light wire have on the regulator?

Thanks again
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Mon 22 Nov 2010 17:05
Morris Mini 1962 - Dynamo - elekie&a/c doctor

As you have a floor start,take the main power lead from the alternator (large terminal)to the B term on the reg.The warning light connection will be to join the D and F small wires (disconnected from the reg) then the small wire at the alternator will connect to small terminal.hth

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Wed 24 Nov 2010 07:43
Morris Mini 1962 - Dynamo - vince208
Thanks for your hepl and I will convert the car to an alternator. I would however be grateful for some further information to help ensure that I don't do any (more) damage.

There is no 'B' terminal on the regulator. The bacolite cover is marked with A1, A, F, D, E. Currently these are connected or otherwise as follows:

A1 - Large spade terminal at the front and small spade terminal at the back. The front (large) terminal has a connection to it consisting of a single spade connector which has two wires going into it. The rear (small) terminal is not connected to a wire.

A - Large spade terminal at the front of the unit and a small spade terminal behind it at the back. Both of these are connected to wires.

F - Small spade terminal connected to a wire.

D - As (A) above (I.e. Large spade terminal at the front of the unit and a small spade terminal behind it at the back. Both of these are connected to wires).

E - As (F) above (One small spade terminal connected to a wire).

Please can you let me know:

Which wires should I:

remove; join together; leave in place?

How should I connect up the new alternator?

Any help will be much appreciated.

Thank you













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Wed 24 Nov 2010 09:16
Morris Mini 1962 - Dynamo - jc2

Type "alternator conversion" into Google;one of the websites on there even includes a circuit diagram.

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