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MG MGB Technical - H.D. Alternator options

I run A/C on my 1970 B and have been running a Nissan 65 Amp alternator to provide extra current for the evaporator and condenser fans, and compressor clutch. I have been through a couple of these, on one the bearings locked up and broke the belt and the latest failure is the internal regulator that will charge under a heavy load but charging is on and off again when A/C is cycled off or turned off. A/C fan speeds vary with the charging mood of the moment and the charge light flickers depending on load and engine speed conditions. The A/C has been running full bore in the Arizona heat.

I am interested in replacing the alternator with a higher output unit or one with greater reliability. The A/C is too much for the original Lucas alternator that failed early on in the installation due to lack of capacity.

Delco? Bosch? Denso? I would like to hear any suggestions that may increase reliability.
Glenn Mallory

Hmm - think I'd be looking for a 100amp alt.
The heater fan and rad. fan would probably draw 10-15a each on full load + ignition + headlights
I'd guess you have all beams operating on high beam so there's possibly 30a there all up for lighting so your 65a alt is maxed out.
My personal choice is to stay away from the popular hotrod single wire alternators. Not because of any faults etc but without a trouble light you get no warning that there's an issue with the alt.
William Revit

My personal choice would be Bosch.

The one on my modern puts out 160-180A which will be more than enough but I'm not sure a standard belt will cope with the drag.

Best of...
MGmike
M McAndrew

This thread was discussed between 02/06/2024 and 16/06/2024

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