MM200 quit

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My mm200 stopped welding during a skidsteer bucket repair. After a bit it would weld.I believe the fan is not working, I have heard it run but not then.I have not opened it yet but will soon. Is there a schematic inside?Anything to look for that is a common failure?I do not have serial yet, but can get it. I believe it to be a later model.Tim Beeker.
Reply:A SN would help but if the fan didn't come on when it should (bad temp switch?) then the transformer temp switch may have opened preventing the contactor from closing (no weld) until it cooled enough to allow it to weld again.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:That is what I am thinking also, where is the fan temp switch located?Tim Beeker.
Reply:On the same piece of aluminum that the fan is mounted on. New one is about $80 if I recall. When mine went south I found a hvac fan switch with the same on/off for a few bucks, works like a champ.
Reply:Great, thanks for the info.Tim Beeker.
Reply:Actually my statement regarding the transformer temp switch cutting out the contactor was incorrect.  The x-former switch (TP-1) and/or one of the temp switches on the output rectifier (TP-2) turns the fan on and the second switch (TP-3) on the rectifier cuts out the contactor at a temperature greater than the fan control switches.So, there are at least two switches (TP-2 and TP-3) you need to check.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!