Lincoln Pro Mig 135-no fan

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I just picked up a used Pro Mig 135 and the fan is not working. It welds just fine, but when the duty cycle kicks in, the fan does not turn on. Two questions here. 1)Is the fan supposed to run constantly when the power is on, or just when the duty cycle kicks in?2)Any ideas on why the fan would not work, and how to fix it? I'm gonna crack the case tommorow and see what I can dig up.Thanks in advance.
Reply:Welder work OK no fan. First, fan does run all the time, The line power switch is turned on.The good news is the welder does weld. That means the fan windings are not open.You have one of two problems. Either the fan bearings are frozen or the fan blades have fell off the fan shaft. For your information this fan motor doubles as a transformer and has a 24vac power out supply that feeds the control pc board. with out that 24 vac nothing works.Soak up the fan bearings in some oil and maybe  you will get lucky. Be careful of the diodes when working on your fan motor. If you need help removing the fan motor Check back and I will give you some directions.
Reply:Thanks.I actually was able to remove the fan motor successfully. The bushings were so tight they would not allow the shaft to spin freely. I polished up both ends of the shaft and got it to spin freely, and now with power applied it sometimes works, but then it will stop, though I can hear the unit buzzing. It' like the electromagnet is pulling it to one side only-whatever it is, it is binding up somehow. I checked voltage across the each of the two pair of wires and there is power, though the voltage kept fluxating on both. (should I be checking AC or DC?)One thing to note, when I removed the stator (is that right? the part that spins) one of the bushings pulled out of the brass retaining spring/clip. Getting the bushing back in was a bear, and now the retaining spring is much looser. Maybe I have too much play and that is the cause for binding. Maybe I need a fan motor now...
Reply:wow. 50 bucks through Norco for a new fan...Gotta have it though.
Reply:although...If I trim off those little brass tabs so they no longer rub on the stator, will that affect anything? It looks to me as if those tabs are merely there for assembly purposes.
Reply:A stator is the windings around the out side. A rotor is the part that spins on the inside. Just for your information.There are 4 connections to the motor, The large connections are 115 volts AC in. The small connections are 24 volts AC out.When you assemble the motor the rotor needs to be centered in the stator. It can move end to end a little. If it moves to much the motor will not run right. Once and a while I run into a motor that spins by hand real good. But soon as power is applied the motor stops. Its your motor and you can try any thing you want. I would try to get it assembled right first and the rotor centered in the stator. Check the bearings and make sure they are centered to each other. You might get lucky. If nothing works you now how to get a new one.
Reply:Okay. Rotor, stator. Been a while since I studied electronics. Thanks.Yeah, it's binding on a slight angle, even though by hand it now spins freely.Any chance anyone knows online suppliers for Jakel motors or even just parts? Since I have to get a new one anyway, I may try enlarging the donut hole in the stator, although I don't know how effective that would be for me as I have no machining tools and would have eyeball getting it round...Hmm. Just a thought...Thanks again, folks.