Need 101 on checking field coils..

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My SAM 400 shows 60 OCV when it should be about 95.  The Lincoln tech I spoke with said to check the field coils first, that both should be around 10 ohms.  So I opened up the doors and there's all kinds of spaghetti in there.  This may not be a simple question, but I hope someone can help.Which two wires do I check to check the field coils?  I've already set the high idle RPM, blown everything out with air, and made sure my brushes were free.  One set of brushes is wearing at an angle, so I have a new set of all 8 brushes on the way.  I don't have a portable field control, but do have a jumper between 75 and 77.  I have 121.4V AC at my outlets at 1800 RPM.My OCV didn't even change by 0.1V before and after performing all of the above.  I also have a new variable voltage pot on the way, as mine appears to not work for about half of it's travel.  For all I know this may be the problem, but in the meantime I want to check my field coils to eliminate them.Can anybody help?
Reply:The variable voltage control is your constant current control for stick mode.The constant voltage  control is your out put voltage control for mig welding. auto terminalInside the generator you have shunt coils and field coils. Shunt coils are large wire and field coils are the smaller wires. Call lincoln tech support and ask for the diagram set.you will need the code number. If you can't read it on the serial number plate, check the barrel of the generator. A lot of machines have them stamped there.
Reply:Thanks for your response, ccawgc.  With the V.V. control set to max, I have to run the coarse control at around 250 amps to weld with 1/8" 6010.  The machine had this issue when I bought it, but I'm just now getting the time to work on it between jobs.  It was also harder than it should have been to get an arc going, which led me to check OCV.  Yesterday I spoke with Lincoln Tech support, and they sent me simplified electrical diagrams.  More detailed ones are supposed to be on the way.  In the meantime, the guy suggested I check "rotor voltage."  Their simplified diagrams don't identify one of the wires I'm supposed to be checking.  I'm supposed to be checking number 1 and number 222.  I've found number 1, on the end of a resistor.  But I can't find 222.  Guess I'll have to wait on the detailed drawings, but I was hoping someone had checked this before.
Reply:Thanks to the detailed Lincoln diagrams, I located wires 1 and 222 and have now verified rotor voltage is 91.5V at 1800 RPM (still only 60 OCV), so I'm back to trying to ohm the field coils.  There is supposed to be a blue and a brown wire coming from the generator I disconnect and check the ohms on.  I'm supposed to check them before they go to the shunt(s) if that makes sense to anyone.  All of my wires have been painted black.Does anyone think they can i.d. them if they saw some pics of the guts of the machine?  I'm not familiar with the names of the different parts of a welding generator, so I don't know where to find the SCR bridge, the 3-phase rectifier bridge, the "lead block," etc.If I describe some of these, maybe you can help me put names to components?1. There's something that looks like a large 3-pole contactor, which would pull in when energized.  It sits vertically so gravity disconnects it.2. Not sure what you call the main switch, it is a 4-position switch that offers straight and reverse polarity each of CC and CV.3. I know the main amperage continuous control is called the "reactor."4. There are two stacked boards, with 3 main wires coming from the generator, maybe #2 size, coming in on one side of the top board, and the two boards sit horizontally directly above the alternator portion of the generator.  They sit between two round copper-wound somethings which are attached to and cant out at angles from the alternator housing.
Reply:I wish I could help more. I have been trying to find info on the computer and not coming up with much. Have worked on one but it was a few years ago. Try scraping the insulation on the wires and see if you get a color change. The SCR Bridge is a pc board. might be what you are describing in #4.Look at your drawings Find where the blue and brown wires connect to and work back from there. I do know if the SCR bridge is not working right, the welder won't work right.
Reply:Update: I found the two wires.  One attaches to a resistor, and one to a diode.  These 2 parts are on the backside of the control panel near the VV and VC controls, within 6" of each other.  Ohm'd out the field coils and got 9.1 ohms, so they're fine.  10 ohms = all OK, 20 ohms = one bad coil, infinite resistance = both bad.