'55 sa200

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well, this is it guys. I got the motor running good, I have upgraded to an elect. idler and have it hooked up the way it says and even called the company I bought it from to make sure its the way i should hook it up. even installed a new rheostat. now, I get small sparks and no idle up. when turned thee rheostat up it seamed to bog the engine down and not idle up. WHAT COULD THIS MEAN. what is the proper hook up on the rheostat (center pin and low pin or center pin and high pin) my guess is center and high. but why is the unit bogging down when I turn the rheostat up. how about the shunts could these be bad, how do I check them?any answer would be great thanks tommy
Reply:Hey Tommy,I WOULD STRONGLY RECOMMENDING THAT YOU NOT RUN YOUR SA-200 BEFORE IT'S CHECKED OUT. The fact that the engine bogs when you turn up the rheostat is a pretty good indicator that the shunt fields are operating.  It sounds to me like the weld output circuit may be shorted.  Operating one of these old machines for more than a few minutes with a shorted weld output can destroy the armature!Check that the heavy weld lead connecting to the current sensor has not been connected to the wrong place. (I assume you installed a current sensor as part of the idler upgrade.)Check that the interpole coil conductors and connections are not touching the series coil conductors or connections.  Nothing should be making contact with chassis ground, (Except the ground terminal of your 115 VDC receptacle.)Make shure the insulators on the brush holders are correctly installed and not damaged.You may want to contact Lincoln.  Ask them to send you the wiring diagrams for your machine, including the internal generator diagram, and go over everything.Good luck,Bob
Reply:You probably have a true short.  Get it fixed before you run the machine again.  It should be easy to find with an ohm meter with some one that knows how to use it.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:I had the same problem.  Make sure everything is extremely grounded.
Reply:i had my high idler and pc board and stuff install and the guy run a ground cable from the idler bracket down to the frame. he said it had to be done.SA-200
Reply:the pc board is mounted to a cross brace on the frame.