M38 Voltage regulator

[horse]

So the end of the story. Still waiting for the end of lockdown so I could get my meter tested, so in the meantime bought another and found it gave much the same reading.

Then running along in the jeep I noticed the Volt gauge was in the yellow all the time.

I tested in the normal way to find no increase in voltage so suspected the generator not putting out.

I then thought I would check the engine earth by taking apart and cleaning, also the fan/generator belt looked a bit slack so that was adjusted.

Ran the engine, no change, still in yellow.

Carried out the Full Field check of the generator from the end of the long cable which was no Volts. I did have a spark when I put the jumper wire onto the hot battery cable on the starter.

Put everything back together a bit despondent.

Started the engine and the Volt gauge when onto the pip after a few seconds.

I then tested the long term overcharging and got 27.9 volts, which is good.

Not sure which bit got her working but it works.

Thanks for the input

[wesk]

Looks like the flashing of the field got the regulator/generator working. Good for you!

[horse]

There is me thinking the flash was a bad thing.

[wesk]

The flash happens when the polarity of the generator's magnet is incorrect. The result is the switching of polarity to the correct orientation. This allows the regulator to properly control the output of the generator.

[horse]

Thanks Wes.

Every day is a school day.