The Classic Mini’s charging system progressed from a dynamo to an alternator during production, and the alternator itself went through several types. Identifying which charging unit is fitted to your car is important when ordering replacement components, as the mounting brackets, fixings, fan belt specification and wiring all differ between types. Fitting the wrong alternator type without changing the associated brackets and belt will result in incorrect belt alignment, premature belt wear and potentially inadequate charging.
Alternator Types
Four main Lucas alternator types were fitted across Classic Mini production. The 16ACR and 17ACR alternators were used up to approximately 1980, identifiable by their imperial fixing bolts and specific mounting bracket arrangement.
From 1980 onwards the A115 and A127 alternators were introduced with metric fixings and a revised bracket. The MPi models from 1997 onwards were fitted with a higher-output 65-amp A127 alternator to meet the increased electrical demands of the engine management system, electric cooling fan, and other ancillaries. The alternator-to-link screw and spring washer also differ between the pre-1980 (imperial) and post-1980 (metric) alternator types.
Fan Belts
The fan belt drives the water pump and alternator from the engine crankshaft pulley. Belt condition should be checked regularly, a worn, glazed or cracked belt will slip under load, reducing alternator output and water pump efficiency simultaneously, which can lead to both a flat battery and an overheating engine. The belt specification differs between engine types: carburettor and SPi models use a conventional V-belt, while MPi models from 1997 use a polyvee belt matched to the revised crankshaft pulley and ancillary drive arrangement.
MGOC Spares Range
This category in the MGOC Spares Classic Mini range covers alternators for all production variants (16ACR, 17ACR, A115, A127 and 65-amp A127), dynamos, alternator mounting brackets with safety guards and dowels, fan belts for V-belt and polyvee applications, voltage regulators, starter relays, charging indicator warning lights and all associated wiring, fixings and mounting hardware.