Hobart Handler 120...Down on power

[chrisl285]

Hello, I recently aquired a Hobart Handler 120 and I am having issues with the welder. The wire feed seems to be working fine, however when I actually start to weld the wire hits the metal and arc's but immediatly stops arcing. Seems like there is not enough power coming from the machine to keep the weld hot, it does the same thing no matter what the fire feed setting is or what the amperage setting is. When I began to take the unit apart I found a brown diode??...not sure if thats the correct name. It was just sitting at the bottom of the welder but I cant for the life of me figure out where this goes. Let me know if anyone can help, or if you need some more info, thanks!!

[Hobart Expert Keith]

Check the two diodes mounted to the aluminum plate(heatsink) above the large transformer. Most likely these will be open.

Keith

[chrisl285]

Thanks...I do remember seeing the 2 diodes there. Can you give me a quick run through on how to check these? I know they are still physically soldered in place and I am assuming that when you say they are "open" the wire inside the diode has opened the circut. Do I need a multimeter to check these? Also can you recommend where to purchase if they need replacing. Thanks!!!

[usmcpop]

Here's a basic tutorial about how to check diodes: http://www.allaboutcircuits.com/vol_3/chpt_3/2.html