Mk I, Correct Factory Alternator

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MkI-Speedwell
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Mk I, Correct Factory Alternator

Post by MkI-Speedwell »

I'm rebuilding a Mk I Cooper S. What would the correct Factory alternator be? I have an externally regulated unit, but could you get an internally regulated unit in 1966.

I'm ordering a harness, and want to get the right one.
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LarryLebel
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Re: Mk I, Correct Factory Alternator

Post by LarryLebel »

I think 16AC but with a 5 pin connector ... rather than a 3 pin one.
Dearg1275
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Re: Mk I, Correct Factory Alternator

Post by Dearg1275 »

Alternator 37H4253 is listed for mk1 cars and this is an 11AC LUCAS alternator externally regulated by a 4TR unit. These alternators did not use a plug in connector but a cable eye for the generated supply and 1/4 Lucas spade connectors for the rest (earth, field and signal)

D
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Re: Mk I, Correct Factory Alternator

Post by MkI-Speedwell »

Hard time finding the correct one. 15 acr, and up easy to find. Used on the Sunbeam Tiger I am told. Maybe Morris Minor.
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Peter Laidler
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Re: Mk I, Correct Factory Alternator

Post by Peter Laidler »

My cop car had a Lucas AC external regulator type alternator fitted plus a knackered spare in the boot for good measure. I machined the internal guts of the old 11(?) AC alternator to take the internals of a 17 (or 18?) ACR with inbuilt regulator. Still works OK. I left the old redundant external regulator in place, wiring blanked off but sort-of wired in to look good.

The old AC alternators gave rise to the mnemonic that LUCAS stands for L oads of U nconnected C rap A nd S older
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Spider
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Re: Mk I, Correct Factory Alternator

Post by Spider »

It does seem they were an 11AC Unit with a 4TR Control Unit, however, I'm pretty sure these were a Positive Earth type.
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Peter Laidler
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Re: Mk I, Correct Factory Alternator

Post by Peter Laidler »

As a matter of interest Spider, as soon as the pommy built Army LandRovers came over to the big Ordnance depot in Bandiana, we had to replace the Lucas alternators for big tried and tested ACDelco ones. Such was the reputation of Lucas in Oz
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Re: Mk I, Correct Factory Alternator

Post by Dearg1275 »

Spider wrote: Mon Jan 18, 2021 5:55 pm It does seem they were an 11AC Unit with a 4TR Control Unit, however, I'm pretty sure these were a Positive Earth type.
Agreed. There were some late 60s vehicles (not minis) supplied with negative earth compatible 11ACs. There may have been special order minis (police etc) that were fitted with negative earth units before alternators were introduced across the range for the mk3s.

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Re: Mk I, Correct Factory Alternator

Post by Spider »

Peter Laidler wrote: Mon Jan 18, 2021 8:20 pm As a matter of interest Spider, as soon as the pommy built Army LandRovers came over to the big Ordnance depot in Bandiana, we had to replace the Lucas alternators for big tried and tested ACDelco ones. Such was the reputation of Lucas in Oz
Mate, I'm not surprised at the swap out. We had a local Lucas factory and much as it pains me to say it, much of what came out of those doors was worse than that from the UK. The only thing left in my non-original cars that is Lucas is the Indicator and Wiper Column Switches and they will soon be going too. It is poor !

Image

Whilst it's easy to look at this and say 'it's old' there's loads of Delco Remy and Bosch units kicking about that are way older and never been apart. I rest my case.
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850man
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Re: Mk I, Correct Factory Alternator

Post by 850man »

Spider wrote: Mon Jan 18, 2021 5:55 pm It does seem they were an 11AC Unit with a 4TR Control Unit, however, I'm pretty sure these were a Positive Earth type.
Nope. Never a std fitment to a Mini. Some 11AC alternators were positive earth and fitted to Jaguars, ie E type, Mk 10 etc.

11AC Alternators were fitted to Works Rally cars, including Minis, but this was a works modification, not a std item.
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850man
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Re: Mk I, Correct Factory Alternator

Post by 850man »

Spider wrote: Tue Jan 19, 2021 12:17 am
Peter Laidler wrote: Mon Jan 18, 2021 8:20 pm As a matter of interest Spider, as soon as the pommy built Army LandRovers came over to the big Ordnance depot in Bandiana, we had to replace the Lucas alternators for big tried and tested ACDelco ones. Such was the reputation of Lucas in Oz
Mate, I'm not surprised at the swap out. We had a local Lucas factory and much as it pains me to say it, much of what came out of those doors was worse than that from the UK. The only thing left in my non-original cars that is Lucas is the Indicator and Wiper Column Switches and they will soon be going too. It is poor !

Image

Whilst it's easy to look at this and say 'it's old' there's loads of Delco Remy and Bosch units kicking about that are way older and never been apart. I rest my case.
Absolute rubbish.
Lucas Australia products were very high quality and last many years.
I work on cars every day that still retain original lucas starters, alternators, generators, etc. They fail due to old age & lack of maintenance, not poor quality.
The modern Lucas reproduced parts that come out of India are rubbish, not our original Aussie made stuff.
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