+8 Alternators

From: Chas Wasser
dot_clear Cincinnati, OH
dot_clear VIN R8287

Last update: October 2, 2002

Chas wrote saying, " I'm trying to replace my Lucas alternator on the 1977 +8 5 speed..

It's a Lucas ACR18 model but its case is dimensionally different that the same model alternator used for the late model MGBs (1978-80). The mounting ears on the MGB case are too close together to work on the alternator mounting platform that's bolted to front of my right hand cylinder head. A real shame cause these units are readily available.

I have the part numbers from my alternator case: 23702E 18ACR 1177 12V
all of these are on a small tag.

The usual suspects (USA Morgan dealers want around $170 for a rebuilt unit) but before I pony up those bucks wanted to find a lower cost alternative. I did investigate the AC Delco GM unit. Got one of the generic 1974-86 3 wire units in the garage right now. But it just doesn't want to fit onto the alternator platform and allow the proper clearances. I think my alternator platform is unique to 1974 thru 85 carb cars. The Moss box and FI +8s use different platforms. I know guys who have made the GM unit work with these era cars, but mine seems problematic.

A German based eMogger did share a Bosch unit that works. It's dimensionally the same, has 55 amps output (even better) and takes up a little less case room. But all he could provide was a european part #. The USA vendors can't make this number work.

Maybe you have sources I don't about the Bosch numbers:

0 986 0 33 860 - 090

the US guys say this is way too many numbers.

The German guy did say that the packing box listed applications for the Europe Ford Seirra, Granada, & Scorpio with 1.8 and 2.0L engines. But those cars were never sold here.

Also checked about having my unit rebuilt locally, but the shop wants around $125-150, assuming the stator and rotor are good, otherwise it will be big bucks."

Unfortunately, I wasn't much help. However, that did not deter Chas. He continued his research and reported back

I promised that I'd get back to you. After much detective work I've learned the following:

1) Plus 8's used three different alternators. They are unique to

a) Moss box cars
b) carb engined cars from 1973 (Rover 4 speed) thru 5 speed Rover interim cars (1977-1982) to last carb cars 1987.
c) Fuel Injected cars (1986 on )

2) Each of these three era +8s have different alternator mounting platforms or brackets. This makes installing alternative units such as the GM Delco alternator, a different engineering exercise for each era car. On my 1977 +8, making the generic (1974-1985 63 amp) GM alternator a real challenge. Hence, I went with finding an interchange from another British car.

3) For later carb +8s like my 1977 +8, the Lucas alternator interchanges with that used on the 1976 Triumph TR6.

Of course the Triumph alternator is available from many sources, often at much cheaper prices than those charged by the USA Morgan agents.

Chas Wasser

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