SA200 generator issue...

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Hi guys...So I bought this machine that had a blown rear seal. The guy I bought it from said he was using it on the pipeline when it happened, and had to put a quart in a day, but all that oil was blowing into the generator and he said by the end of the job, he had to turn the machine to its highest setting just to burn 5/32 6010.So I welded with it and didnt notice anything wierd, so I bought it, took the motor out, cleaned up all the visible oil I could see, replaced the seal, reinstalled the motor, got it to run, but it doesnt weld as hot as it should. It welds fine, but I don;t get the amps I should using the same settings that I use on all the other SA200 machines at work. I'm not sure it would even burn a 3/16 rod, since I have it up so high just to burn 5/32. So basically it's doing the same thing it did to the guy I bought this machine from. What could possibly be causing this???This has got me stumped. Any words of wisdom would be appreciated!!!
Reply:Welcome to the forum hotshotwelder.A couple questions.1) How did you go about cleaning the oil from the stators and rotors?  A hot pressure wash with grease cutting detergent or major washdown with Brake-Kleen or air drying solvent would be in order to get all the oil out of the windings.2) Did you dress (clean) the commutator rings on the rotor and brushes?  If not, the oil deposits may have been 'baked' onto the commutator rings/brushes limiting the field current being supplied to the rotor thus limiting the output current.Just my first thoughts.DuaneMM200 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:Hi Duane!!!Ok, so, since this was the first time I ever have worked on anything like this, I was afraid to use any kind of cleaners on the generator assembly so I asked my dorky electrician buddy what would be safe to use on electronics, and he said contact cleaner. It didn't do much, but for the rookie that I am, I didnt want to make anything worse by using something I shouldn't.So it's probably not near as clean as it should be inside.For your second question, by cleaning the commutator rings, do you mean using a commutator stone on the commutator to make it shiny again? I haven't tried that yet, but it doesnt look like the oil was caked on there like it was in the back of the generator. Now someone just told me tonight that these machines have 2 sets of brushes, but when I remove the cap on the front of the welder, I only see the 1 set (2 brushes) on the commutator. IS there another set of them somewhere else??? I should also mention that, due to my lack of experience, I only pulled the motor. I didn't tear apart the generator since I don't know crap about them. Thanks alot for the response! I already feel better knowing that there might be some people out there that know more about this than I do lol.
Reply:Well I assure you there are plenty here that know a whole lot more about them than I do.Do you have any manuals for the unit?  If not, you can download the operations manual here http://www.mylincolnelectric.com/Cat...ualsearch.aspx that has a parts breakdown so you can somewhat see how these things are put together.  You'll need to enter the unit code# to get the right one.Yes, that's what I meant regarding the commutator rings and yes they have two sets of brushes - one for the exciter rotor (armature) and one for the welding generator rotor.  The exciter brushes are on the end of the unit under the 'hat' and the generator brushes are about midway up the unit under what's refered to as the 'generator end shell'.Take a look at the generator brushes and commutator rings and you may want to consider pulling it down again to give the inards a real good washing to get the rest of that oil out of there.Oh, and here's http://billswelderrepair.com/Engine-Drives.html a good place to get information too.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!