The Fordson Tractor Pages Forum

Hi. Can any one tell me how to test the voltage on a Super Major Voltage Regulator with the DEAF terminals. In the Manual I have it says disconnect the A and A1 terminals and connect together then connect negative lead of voltmeter to these leads and positive lead of voltmeter to earth then start engine and increase revs until needle flicks and steadies on volt meter. I don't have an A and A1 terminal, I think this may be on earlier Power and Diesel major regulators, would I just disconnect the A terminal?. Also the new type regulators can you adjust them, there are 2 rubber plugs on the side with 2 crews underneath are these adjustment crews?
Hopefully someone can help

Thanks in advance.

The late regulator is sealed, I do remember something on adjusting it but I don't know where. Just connect the voltmeter to terminal A as you say. There are screws beneath the rubber, but I can't say what each one does. Don't adjust them unless you know what they do.
Sandy

Billy26F5 wrote: ↑

Sat Sep 25, 2021 9:18 pm

The late regulator is sealed, I do remember something on adjusting it but I don't know where. Just connect the voltmeter to terminal A as you say. There are screws beneath the rubber, but I can't say what each one does. Don't adjust them unless you know what they do.
Sandy

Hi Sandy many thanks. After the loom burn out incident this week just want to make sure the voltage is in limits and not to high so shouldn't need to adjust.

I would doubt the regulator being able to do that, as the dynamo would suffer as well. It's almost certainly bad insulation somewhere.
Sandy

StuP
Start the engine and idle it.
Connect volt meter across battery terminals and note reading -- good if above 12 and a bit.
Max rev engine -- good if 13 plus. Bad if 14 plus.
Turn on high beam lights with max revs. Good if approaching 13 -- bad if much over 13.

If it is regularly overcharging the battery will emit over gassing and the battery terminals will get a white powdery appearance.
Pavel

Here you have full details on testing the earlier regulators, it should help.
http://www.fordson.se/7_El_Verkstadsmanual_191-224.pdf
http://www.fordson.se/8_9_Broms_sl%E4p_ ... 01-010.pdf
Terminal A1 goes to BATT on the ignition switch and terminal A to the battery (via the ammeter on Major's, directly on early Power Major's). Later sealed regulator fitted Major's have terminal A going to the battery and a separate wire from there to BATT on the ignition switch.
Sandy