SA250 No power at all...

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ok, heres the scoop...The welder is old as the hills, its been sitting at the end of my driveway before i moved here 4 years ago, landlord said its been there for years before that.  So lets say 8 years of storage in the weather (side covers were off)The landlord said that the welder did work at one point in time.  But after one quick glance at it i knew it was not in running order!I gave lincoln all the info off of it and got the correct wiring diagrams (you know its old when the diagrams are hand written!) and proceeded to fix all of the wiring f-ups.  their were alot of splices and wires going to places they shouldnt have!After straightening out all of the wiring and busting the engine loose, it fired up and ran like a top!Now for the issue...  No power at all (AC or DC) other than the 12v circuits for the engineIm no guru at all as far as it comes to generators so i dont really know where to go from here (what to check, what to do).  i have heard of and read up a bit on 'flashing' it, which sounds like that might be whats needed...Any ideas guys?
Reply:If you're absolutely sure the wiring is now correct, make sure the brushes are free in their holders, clean the slip rings/commutator and flash the field with a 6-12vdc battery.To flash the field, simply apply the 6-12vdc to the brush circuits (+ to + and - to -) for a couple seconds.  You've stated you have all the wiring diagrams from Lincoln so you should be able to see where you need to/can apply the flashing voltage.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:Yes, everything is now wired 100% to the diagrams that lincoln sent me.  Brushes are free and cleaned up.The only thing that i am not 100% sure on, is the +/- wiring on the slip rings.The diagram i have does not give me orientation of which one is +/- so i just went with the wiring that was already there, which was positive to the rearward ring.  But... that may be incorrect...I want to get that clarified before i go as far as flashing it, because it probably isnt going to do anything if its wired and flashed backwards!
Reply:Yes, the + slip ring is the outboard one with the - closest to the rotor iron.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:perfect, i will try flashing it tomorrow after work and see what happens...Now, Failing that being the problem.  what would i look at next?  what should i see for voltage on the field circuit?Thanks for the help!  Hopefully i can get this clunker running, im not much of a fan of arc welding, but it would be nice to have this thing going so i can work on my skills (got a buddy thats a cert welder that can help me!) and the price tag was right.... Heck, might even sell it if it works good (welder buddy is looking for another machine for backup) and go buy something else, i hate not having a welder!Last edited by YkDave; 03-31-2010 at 12:25 AM.
Reply:Other ills could be as simple as a dirty/tarnished Fine Current Control rheostat wiper/coils and as serious as an open field shunt coil or rotor winding.Field voltage should be 100v+.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:I flashed mine the easy way. I started it off the output studs with my other welderDisclaimer; "I am just an a$$hole welder, don't take it personally ."
Reply:LOLWell, lacking the other welder and with my luck of getting fried or frying the machine, im going to have to pass on that option!Just got off work, going to suit up and head out there in a min to tinker on this thing
Reply:Well, no dice....I assume that i needed to isolate the brushes from the armature and apply the flashing power directly to the slip rings (from what i have read)?  which is what i tried...Using my trusty old analog multimeter (my good digital one is at work), i noted the needle hover at a couple volts for about 10 seconds then fall back down.  that could have even been from the vibration...
Reply:Well, i tried flashing again....Might be getting somewhere....  Getting a steady whopping 5v on the field circuit now!
Reply:Here's the process as written in the SA250 manual:FLASHING THE FIELDSAC Auxiliary Power:I. Stop the engine welder and remove the cover fromthe exciter.2. Turn the "Fine Adjustment Control" (rheostat) to" 100" on the dial.3. Using a 12 volt automotive battery, connect itsnegative terminal to the negative brushholder. Thenegative brushholder is the one nearest to the rotorlamination. See the wiring diagram. With the engineNOT running, touch the positive battery terminalto the positive brushholder. Remove thebattery from the circuit.4. Replace exciter cover. Start the welder and the generatorvoltage should build up.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:yup, i found that little tidbit in my manual and thats what i tried the second time.  Still nothing great, but i am getting a steady low voltage still...
Reply:Have you checked the rheostat yet?  You can jumper the terminals to by-pass it if it's bad to check for full output.I'm sorry to say I don't have any resistance values for rotor, armature, coils, etc. so I would suggest giving Bill or Kaye a call at Bill's Welder Repair at 405-232-4799.  Both are extremely helpful and know the SAs inside and out.There's also a ton of info on their website - http://billswelderrepair.com/home.htmlLast edited by duaneb55; 03-31-2010 at 11:18 PM.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:i have checked the rheostat (it appears to be functioning 100%) and even tried bypassing it, to no avail...guess ill give those guys a call tomorrow and see what their thoughts are!
Reply:Didnt get a chance to call those guys yet.  Its a holiday for us today, i would assume its the same for you guys?Anyways, i went out and started pulling things apart and checking things!The main brushes for the welding gen are grounding out, i assume this is not good...With the exciter circuit isolated from everything else, i do see a rise in voltage, now seeing about 15 volts in the exciter field.  When the wiring is hooked up to the bridge rectifier it instantly drops to a couple volts, same if the 2 wires are re-attatched to the main brushes.
Reply:One thing you need to check it the Rectifier.. It's the little square box on the other side of the rusty screw on panel (it's the only rusty screw) drop the bottom panel and look for the white wire that should be piggy backing a yellow wire. It rusts out and falls off. I just tied them together with a new spade connector and I have 110V and welding current.. (Prior to that I only had a small fizzle spark on the weld leads. Good luck.. Croz Custom Metal Fabrication.
Reply:checked and even replaced the bridge rectifier (mine actually has a brown wire from the welding gen piggybacking the black IIRC from the aux gen).  no-go at all, still a couple volts is all i can get out of it!I guess it would be good for powering a small clock or something...