Need wire feeder help

[camire09]

Hi all,
Need some help. I have a model S-64 Wire feeder has been giving me some problems for the past few months. We have it set up on a production turn table and it does about a 8" dia. circle weld. It is not all the time but during a weld the weld will get wide and hotter till it burns through. Also not sure if this has anything to do with it but I can not turn down the potentiometer. I can go higher but I get down to about 600 and it goes crazy. Think that could be it? Or maybe one of the boards?

Any help would be greatly appreciated.

[cruizer]

Whats the power source and wire stick out.

[camire09]

Miller XMT 304 & 5/8"
The weld will go from about 1/2" wide to about 3/4" sometimes it will even go back down. We have to of these welders doing the same job. First we thought it was the turntable but when I switched just the wire feeder the problem followed.
I was wrong the Pot. doesn't really change much, up or down stay around 600 until you turn it all the way down then the screen will read 0 to 145

[cruizer]

Really you should have no more than 3/8 stickout, whats happening is that the machine is trying to monitor stickout so its increasing and decreasing voltage to maintain the arc and its having tough time doing it with that much gap

[weldbay]

If the pot does not controll the speed then replace the pot.