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Morning all, how do I tell if the dynamo has had it? Whilst the car was in for MOT the workshop charged the battery and the car started on the button no problem. The last few times starting though it has seemed as if the starter motor has stuck and won't engage but the car starts by bumping straight away. I took the starter motor off yesterday and lubricated it but the problem is still there with the power running down. I've took it on a fairly long run but it makes no difference - switch off and it refuses to turn over.

Dynamo had it?

Cheers. Tim

My first check with it running,put voltmeter on battery and you want to see approx. 13,5 volts

Easy test is to remove it from car apply earth to body and connect live to both terminals, should spin up as a motor if it does this problem is likely with control box. There is a guide on this site somewhere with test procedures

If the ignition light goes out that usually indicates all is well with dynamo. Have you checked that the battery isn't being over charged?

I'd also check the engine earth strap and stater solenoid.

Many thanks for the replies!

Simon, the ignition light stays on even when revved so i would say that theres a good chance the dynamo needs attention!


Tim

My ignition light stayed on, dynamo was fine it was just the points in regulator box needed a good clean. There are a few videos on YouTube from moss Europe that explain how the system works but all you need to test it is a basic voltmeter

Could be a bad battery. Have it load tested.

More likely to be the regulator than the dynamo, as mentioned previously.

But...never say never !

Might be worth checking the springs holding the brushes (in the dynamo) are intact. I had the same thing happen to one of my old Minis and I found one of the springs had rusted through.