Miller Thunderbolt 225v crank won't move

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I have an older Miller that welds just fine.  I've heard they are a rugged, long lasting piece of equipment, and I feel good about having one.Recently I pulled out the welder, and it wouldn't crank for me.  It turns on.  It welds, but I can't adjust the amps.  The crank is stuck.  I can wiggle the piece that slides up and down in the middle of the condenser (I think that's what the big square with a hole in the middle is).  So there doesn't seem to be a problem with it rusted together or anything.  I think it's just the crank rod that is stuck.  I can't turn it.Has anyone ran into this problem before?  What did you do?
Reply:http://www.millerwelds.com/om/o116j_mil.pdfIf you click this link, you go to the manual for this unit that I have.  Scroll on down to where the exploded diagram of the parts is, and you can see where the rod from the top of the unit goes down into the unit.  At the end of the rod right around #15 is where my problem is at.  That is where the rod is not turning.  Something to do with that are prevents the rod from turning, so the amperage piece won't slide in and out.
Reply:That's the main transformer and the part that moves up and down is the shunt block (#12).It sounds like the shunt lead screw (#11) is rusted to the lead screw nut (#10) located inside the two piece shunt block (#12).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:#11 is just a screw that holds the #12 two piece shunt block together.  That would have nothing to do with why the #9 screw doesn't turn allowing shunt block to travel up and down.  I just can't get the amps to go up or down because that 9 screw won't turn for some reason.  I was hoping that someone else had a little know how in this situation.
Reply:Hi "Gentleman"Duane knows more about these repairs than most on this board. Maybe instead of getting hung up on the item numbers think about what he is saying, check the lead screw and nut to see if they are rusted frozen or stripped.Regards,MarkLast edited by BorderBrewer; 08-09-2012 at 11:54 PM.Reason: spellingMillerMatic 135Handler 210 w/ DP3035 SpoolgunLincoln AC-225Primeweld TIG225xEverlast Power Arc 200Weldcraft TIG rigSmith American Classic O/AEvolution Rage 2 SawTD Cutmaster 52Miller Thunderbolt with HF Box
Reply:Never doubt the "DUANE"Last edited by dumb as a stump; 08-09-2012 at 11:53 PM.Reason: stupidMiller thunderbolt 250Decastar 135ERecovering tool-o-holic ESAB OAI have been interested or involved in Electrical, Fire Alarm, Auto, Marine, Welding, Electronics ETC to name a just a few. So YES you can own too many tools.
Reply:Okay.  Understood.This transformer is very heavy, and if I unbolt if from the casing in order to get inside the shunt block to check for rust, it's going to be murder getting it back into place to get it to bolt up in there again.  Duane, have you ever disassembled one of these so you could get into the shunt block and take a look?  Did you have to take out the whole transformer, or was there an easier way?  I think this project is hopeless, and the unit is probably worth more as copper scrap than as a welder.  I'm not seeing any easy way about doing this.  I'm usually the intelligent kind that just figures out stuff on the fly as I study the problem, but I'm not seeing an easy way out of this.
Reply:"I think this project is hopeless, and the unit is probably worth more as copper scrap than as a welder. I'm not seeing any easy way about doing this."C'mon man, the Thunderbolt will always be worth more as a welder than as scrap. You can fix it. These welders are built to be serviceable and if you work through this you will be passing this welder on to your heirs in your will. Once it's fixed, clean the insides every six months and grease the shunt block and lead screw. No more troubles.Regards,MarkMillerMatic 135Handler 210 w/ DP3035 SpoolgunLincoln AC-225Primeweld TIG225xEverlast Power Arc 200Weldcraft TIG rigSmith American Classic O/AEvolution Rage 2 SawTD Cutmaster 52Miller Thunderbolt with HF Box
Reply:Originally Posted by 1GentlemanOkay.  Understood.This transformer is very heavy, and if I unbolt if from the casing in order to get inside the shunt block to check for rust, it's going to be murder getting it back into place to get it to bolt up in there again.  Duane, have you ever disassembled one of these so you could get into the shunt block and take a look?  Did you have to take out the whole transformer, or was there an easier way?  I think this project is hopeless, and the unit is probably worth more as copper scrap than as a welder.  I'm not seeing any easy way about doing this.  I'm usually the intelligent kind that just figures out stuff on the fly as I study the problem, but I'm not seeing an easy way out of this.
Reply:Haha, alright, I'll give it a go.  I'll return with what I find out was wrong with it.
Reply:Hi, Gentleman,I've had 3 of those, 2 AC only and 1 AC/DC. They are tanks and easy to work on. I'd sure start with Duane's advice, then keep on working on it and lubricating it until it works. The fact that it was working fine last time indicates just some rust or something easy to fix. Besides, it is a fun project to take it apart and satisfying when you get it fixed. Post your location in your signature block and maybe there is a member close enough to help.Also, the very early models were copper, but later they are aluminum, so scrapping may not bring as much as you are thinking. Either way, I'd rather have a working welder than $15-20 pocket money.I'd also suggest you look at page 6. You may need to loosen the #2 screws, and try to get some grease on the sides of the shunt block. May take a little time to get it moving again.Good luck, and post some pictures.Burt _____________________Miller Syncrowave 250Millermatic 211Miller 375 Plasma Cutter Hobart Handler 12010FtDrillBit.com
Reply:Originally Posted by 1Gentleman#11 is just a screw that holds the #12 two piece shunt block together.  That would have nothing to do with why the #9 screw doesn't turn allowing shunt block to travel up and down.  I just can't get the amps to go up or down because that 9 screw won't turn for some reason.  I was hoping that someone else had a little know how in this situation.
Reply:Yes, its aluminum wire not copper and yes Duane is right.So tell us where you are at if you need help, someone maybe close by.