MM 200 questions

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Hello guys, I recently purchased an old millermatic 200 for $750. Condition is pretty good, and I've heard nothing but good things about this machine. I've used 251s/252s at the school where I go for welding technology, but so far this mm 200 feels a little different and I could use some help dialing it in. With the 251/252 I can get that beautiful sizzling bacon sound but so far with the 200 I've gotten very loud pop pop pop. Just seems off.  First one of the things that intrigued me about this unit was it already had a 50 foot power cable, which I needed to actually run it to where my 230v plug is. I'm not sure what gauge wire is in this power cord. Does this affect my voltage. As far as when I set it to 23v is it actually at 23v or more/less due to the 50ft power cord? Or could the previous owner used to small or too large of gauge wire and would that affect it?Secondly, and this May be due to the first question, but I'm doing a ton of 3/16 carbon and the recommended settings do not produce a bead that I'm used to seeing.  Very convex and poor toe fusion.  It recommends: high 2 voltage, and a wfs of 48% (using .035).  I've messed around with the settings a lot and have found that im actually in the wfs range of 80%-90% to get a better bead but still not as good as I'd like. Would just like someone to shed some light and maybe explain what I'm seeing here. Thanks all, any help much appreciated Brett
Reply:Check your input voltage and verify that the machine is linked for the correct voltage. There is a 200 volt and a 230 volt link.
Reply:Find out what gauge the power cable you have is made from. If it is #8 or better you are OK.If the MM200 is welding poorly the caps may have to be replaced. There are several threads here dealing with cap replacement and MM200 maintenance in general. It could also be as simple as a bad ground clamp or cable. Carefully check the condition of the clamp and both ends of the work cable.Also check where the gun cable connects to the machine.JohnA few weldersA lot of hammersA whole lot of C-clamps
Reply:The door chart on my mm200 is way off, so dont rely on it for set up. The taps can fairly accurately be  set, just take the lowest tap, low 1 and number that as the lowest rated voltage, 10vdc IIRC. Then add 2 volts for each higher tap. 6 low and 1 high are the same voltage so your taps are 10,12,14,16,18,20 on Low, and 20,22,24,26,28,and 30 high. The lugs inside the machine where you plug the cables in are notorious for arcing. Unbolt them, sand them bright and shiny and rebolt, same with the cable on the drive roll. I also did it on the lugs on the back side of the voltage selector. Put a new liner in it, set it up by voltage and the pull the trigger for 6 seconds, measure the wire, multiply by 10, and that will tell you what your WFS is. Fine tune from there. Also check the connections inside the plug, and your wall receptacle. I had an issue recently and found  a loose connection there. Also, as was mentioned check the voltage link. You can download a manual on the millerwelds.com site.