Miller big 40 won't weld

[Gary p]

I'm new to this sight trying to find some help with my big 40 I used it a week ago welded fine started it today and it doesn't produce any weld output but will produce 110 out of receptacle checked brushes they are free not sure how to check other components any thoughts thanks in advance this is a late 70's machine

[HighFly27]

You Can Down Load the Big 40 Operater Book from Miller Web Site

Hello Sir,I have a Miller Big 40 Welder, along with other Miller welders. I wrote down my Serial Number and Model No# and down loaded the Operator book from the Miller Web Site. The Operator manual has/ or could have some Trouble Shooting Information in the back of the operator book.

Also, a man on another welding forum emailed me a higher ended service guide for my Trail Blazer 250 G. This Service Manual had a complete listing of Voltage Checks, etc., and it worked great to trouble shoot my Trail Blazer 250 G. Perhaps, someone (here) can help you more... if they had a Service Manual for you Big 40 Welder and emailed it to you.

Avery