66 Cooper S - Correct Alternator

[MkI-Speedwell]

I am thinking of installing an alternator to my Cooper. I have two NOS 15 ACR tagged units. I 'm not savvy on the fitting of an externally regulated alternator? Is it just a matter of the correct harness, then plug and play. Does the Control Box stay, and a regulator put in place?
What unit is Factory correct.

[Tds76]

Australian Cooper S Mk2 had 15AC with external control.

See below from Leyland Oz workshop manual.

36C162B0-7A15-4414-BF3F-5CD609BCB640.jpeg

Full diagram at Ausmini.

http://www.ausmini.com/forums/viewtopic ... 25&t=94122


Cheers, Paul.

[850man]

Fit an internal reg Lucas alternator ie a 17acr and you will not have to bother with all the extra wiring & external reg that a 15acr has.

[Dearg1275]

In the UK where an alternator was fitted in 1966 ( typically for police vehicles) it was an 11AC. This together with a 4TR control unit, 6RA field isolating relay and 3AW alternator charge indicator unit. BMC’s descriptions not mine. If you are going this route the problem will be finding good items. There are repro 4TR & 6RA unit’s but of unpredictable reliability. If you can find NOS that’s favourite but not infrequently they have been put back in there box and return to the stock shelf because they didn’t work. The only way to know is to build your system and see if it works.

The 11AC puts out 44 amps so if you get it all to work it’s well worth while. If you need the workshop manual details let me know and I will scan them for you.

D

[Ronnie]

These might help if you go with 11 AC - earth http://mk1-performance-conversions.co.u ... ac-neg.pdf
11AC + earth http://mk1-performance-conversions.co.u ... ac-pos.pdf

[MkI-Speedwell]

Thank you for the information! I appreciate it.

[ivor badger 3]

Remember that when the car was built, it was + earth, That is why at the time it was an AC alternator with external regulators.