Alternator Spec

[Peted7202]

I have an Magneti Marelli alternator rated at 85amp. Could this be used on the Minor?

[Bill_qaz]

From the pictures it would need a pulley change to v belt and check alignment on installation. The W terminal for the warning light looks to be missing. Far simpler to just buy a suitable alternator for circa £50 that's a direct fit.(same as mini) 18ACR 45 Amp plenty enough output for a minor.
But your decision

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[svenedin]

Or even simpler, stay with a dynamo

[philthehill]

The alternator under discussion is of the type fitted to the MPI classic Mini.
I would suggest that a single 'V' belt would not efficiently drive the Marelli alternator. The resistance to turning will be quite high thus the need for a multi 'V' poly drive belt.
You would at least need the multi groove crankshaft and water pump pulleys or toothed drive belt set up and mount brackets.
Even a Lucas lower output alternator is prone to belt slip and squeal when asked to produce power especially after a engine start.
https://www.scparts.co.uk/sc_en/british ... relli.html

https://www.scparts.co.uk/sc_en/british ... on.html#49

https://www.scparts.co.uk/sc_en/british ... ys.html#22

To be honest a lot of trouble and expense for little gain over a Lucas 18ACR alternator.

[Peted7202]

Thank you.

[Bill_qaz]

To be honest a lot of trouble and expense for little gain over a Lucas 18ACR alternator

Totally agree Phil

[Bill_qaz]

Or even simpler, stay with a dynamo

How do you know he is replacing a dynamo?

[oliver90owner]

PTH is right on the money re driving that alternator. A single narrow section V belt would soon be shredded if attempting to generate a kW. Automotive alternators are not the most efficient, so the single belt would need to transmit around 1 1/2kW - that is without the water pump and fan. Especially as that potential 1kW could be generated at a low belt speed!