Testing Dynamos

[paul.jameson]

If you disconnect the wires from the dynamo, then sort out D and F on the dynamo you will get maximum output. So this serves as a test that the dynamo is working - which yours seems to be.

I am tempted to question whether your ammeter is working properly.

Re-connect the dynamo leads and turn the headlight on. Start the engine and see if the light brightens when you increase revs. If so, get a new ammeter.

[JohnReilly]

I have tested everything and all seems OK but no charging current. The ammeter checks out, lights do not get brighter when revving up. Dynamo putting out in excess of 15V. wiring continuity between points OK.
I think the regulator is not working.

[paul.jameson]

New electronic regulators usually work because they are tested before despatch.

So the possible problems seem to me to come down to either low battery voltage or incorrect connections. Whilst the old fashioned original regulators would work with a flat battery, or without one altogether, an electronic regulator needs some battery voltage to work. Quite how much will no doubt vary from regulator type to type but a quick check of the battery voltage is worthwhile and if you find it less than 12 volts, put it on charge for a few hours.

The other possibility is incorrect connections and two thoughts come to mind here. One is that the connection order on Lucas regulators changed from FADE to FAED at some stage so if you have mounted your electronic regulator in an old Lucas regulator box, check these connections. The second is whether you have the correct polarity from your dynamo. It is just possible that you may have inadvertently managed to reverse this so again, a check is worthwhile.

Even if you have had an incorrect connection, an electronic regulator usually has some sort of protection so once you get things right, it will normally work. But, as ever, I may well be proved wrong on all counts!