Lincoln SA-200 no spark

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I have a Lincoln SA-200-F-163, the engine is running, but when I strike an arc there is only a small trickle of voltage output.I have cleaned the brush guides and armiture.  If anyone has any suggestions, I would appreciate it.
Reply:Sounds like the welding generator is not getting exciter current.  That could be caused by many things, bad rheostat, bad connection in the exciter circuit.  non-functional exciter, or open shunt coils in the welding generator.I would first try moving the rheostat up and down several times to wipe it clean.If that doesn't help, check to see if you have about 120 volts DC at the receptacle on the front of the SA-200.If you don't, check for DC voltage across the exciter brush terminals.If the voltage is about 120 VDC check the wiring and connections.  Lincoln will usually email or fax wiring diagrams if you contact them and ask.  Make sure you tell them the code number for the welder.If the voltage is zero, or measures in millivolts, you could try flashing the fields.  This can be done with a 12 volt battery or any other DC power source.  (Don't use over 120 VDC.)With the engine off, raise one brush off of the exciter armature, connect the positive lead to the right brush terminal and the negative lead to the left brush terminal.  Apply DC voltage for about 3 to 5 seconds, disconnect the DC  power source, lower the brush onto the exciter commutator and start the engine.If none of these things help, the problem may be an open shunt coil, exciter coil, or a bad exciter armature.Good luck,Bob
Reply:Thanks Bob, I will give it a try.  Tony
Reply:Does your machine attempt to go to high idle when striking an arc? If this does not occur you will only get OCV at the stinger (sparkle). Check the reed switch. This sits in a copper pigtail behind the output stud and the top of the selector switch, with a wire coming from each end of the pigtail. One of these wires goes to the idler board and the other goes to case ground.When you touch stinger to ground this switch feels the draw, closes and sends 12v to the board, idling your machine up. When you break arc the switch opens, dropping out the 12v to your board, the board grounds out and idles your machine down.Can you flip the switch to hi and get weld? Do you have 110v at the plug? If you don't have 110 you will not have weld. Answer these questions and I will help you further.