Well it's not humming, so the diodes are bad. I don' have a volt meter that tests diodes. if I do a resistance test that will work too, right? Sorry I'm a new at this.
Yes, you test diodes by measuring the resistance in both directions. It should show high resistance with the leads connected one way and low with the leads swapped.
Leave the transformer disconnected and measure all 4 diodes (two on the one plate and 2 more on plate behind that one.)
At least the transformer wires need to be disconnected as it will act as a short on the diodes. The output has a big capacitor, so that will cause the readings to take a long time to settle.
If your meter has a diode test function, use that. Otherwise, a low ohm range. The value will not be that significant; just that it measures alow resistance one way.
Do you know where I can get these rectifier diodes cheaper, because Lincoln wants $30.00 a piece for them. If so what size do I get? Would bigger amp be better? What do you recommend?
Lincoln part number from schematic:
rectifier diode negative M9661-39R
rectifier diode positive M9661-39
On the diode itself reads:
9914
m9661-40 Italy