Morris Minor Owners Club

hello all

I am having some trouble with my voltage regulator. It is overcharging.

It is charging at 16,5V which is 2,5V to high in my opinion, and it make the battery sizzle, which is not very nice.

Lights are nice and bright though (and I haven't had any go so far!)


How do I go about adjusting this?

I do NOT want to go the alternator route

I think the Haynes BoL has a section in it describing ghow to adjust the regulator (can't lay my hands on my Haynes right now to check), and the BMC workshop manual certainly does.

You have to adjust the contacts in the regulator, which is done by twiddling screws on them - I also seem to recall at least one adjustment has to be made within 30 seconds of firing the engine up, so your overcharged battery might come in handy if like me you can't get it spot on first time!

Page 136 in the Haynes manual ;)

Just a little safety tip here. If your regulator is over charging that bad, wear safety goggles just incase the battery bursts or vents so much hydrogen there is a flashover.

The regulator is likely to be knackered - you can try adjusting it (but why did it go wrong?) - but would be better and easier to just fit another! Is it possible you have s hort between the thin wire and the thick wire to the dynamo - if so, this will give high voltage just as you are seeing - I used to have a switch on my Rally Minor that did just that - for max dynamo output when running extra lights!

Yes replace and forget,the 1970 Reliant Regal i was using a few months ago didnt charge at all,the previous owner said "ive changed the regualator but it didnt work"yes he had changed it,but he had just put another old one on!i bought a new Minor one(same part)and it was a total cure.For the cost of a new one(less than £20)it would be far easier to do that than attempt to fix the old one,as its likely to be toast anyway.