Morris Minor 1098cc Higher Amp Alternator

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Grover267
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Morris Minor 1098cc Higher Amp Alternator

Post by Grover267 »

Hello Everyone
I have a Morris Minor 1098cc van with a 45Amp Alternator. Problem is that most my driving is around town which means alternator
struggles at low Revs.

Does anyone know of a higher Amp alternator that would fit the Morry 1098cc?

Your help would be much appreciated.

Johan :)
59Elva
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Re: Morris Minor 1098cc Higher Amp Alternator

Post by 59Elva »

Smaller pulley?
Bill B. ‘59 Pickup USA
Andmurph
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Re: Morris Minor 1098cc Higher Amp Alternator

Post by Andmurph »

These guys do an 18ACR 65 amp that would fit.

https://bbclassics.co.uk/products/18acr ... 8663630126
1972 Morris Minor 1000 pickup
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svenedin
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Re: Morris Minor 1098cc Higher Amp Alternator

Post by svenedin »

I am a bit puzzled as to why you need so much power. I have always found the Lucas C40 Dynamo at its modest 20-25 amps more than enough.

If most of your driving is around town in traffic or at low speeds your alternator should still be more than sufficient. This was the reason alternators were fitted to the late Minor police vehicles. The dynamo did not generate enough power at idle or driving around town. Those police vehicles had two-way radios that used a lot more power than a modern electronic radio receiver.

Are you sure that:

1) The belt is tight enough and is not slipping? Alternator belts need to be considerably tighter than dynamo belts.
2) Is the alternator actually working properly. Have you tested its output?
3) That it has the correct pulley. If the pulley is too large the alternator will spin too slowly.

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
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geoberni
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Re: Morris Minor 1098cc Higher Amp Alternator

Post by geoberni »

Grover267 wrote: Sat Aug 15, 2026 11:02 pm Hello Everyone
I have a Morris Minor 1098cc van with a 45Amp Alternator. Problem is that most my driving is around town which means alternator
struggles at low Revs.

Does anyone know of a higher Amp alternator that would fit the Morry 1098cc?

Your help would be much appreciated.

Johan :)
There should be no reason why a 45A Alternator is failing to provide the power you need, if it's correctly installed and serviceable.
That's double the original Dynamo output.

So let's get the whole story before considering fitting something larger.

How long have you had the car?
How long has the alternator been fitted?
When did this failure to keep the battery charged start happening?
Have you actually checked the output of the alternator at idle, is it giving around 14v ?
If you haven't got a voltmeter, put the headlights on and see if they are dim at idle and then get noticeably brighter if you slightly increase the revs.
Basil the 1955 series II

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oliver90owner
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Re: Morris Minor 1098cc Higher Amp Alternator

Post by oliver90owner »

I am guessing it is the AVC that is at fault. A simple and cheap job to change it.

I had a diesel Corsa, back in the 2010s, that stopped charging if the revs fell even to somewhat above idle. A PITA as the lights always noticeably dimmed at any, and (almost) every, slow speed junction as well as when idling in traffic.

I cannot now recall whether I ever changed the AVC but, as recall, the alternator was changed out at some point (expensive as it also included the power steering pump drive). It annoyed me at the time as the charging issue was eventually traced to a damaged wiring harness before I bought it. Possibly why it was cheap at auction - but it was probably the worst car I have owned for reliability problems.
les
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Re: Morris Minor 1098cc Higher Amp Alternator

Post by les »

I’m surprised you didn’t try your often quoted diagnostic procedures before replacing parts ! :o

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