Magneto not developing spark to spark plug.

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I have a 1963 SA 200 that has been sitting for 30 years.  I am using the crank to turn the engine over.  I've got a spark plug connected to the mag. laying on the exhaust manifold and get no spark.  From what I know about mags (which isn't much) I should be getting a spark when using the crank.  This is a Fairbanks-Morse mag.  Does anyone know of a mag repair person in the west central part of WI.Thanks!

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Reply:The magnic may need to be recharge. Dave

Originally Posted by Erniet

I have a 1963 SA 200 that has been sitting for 30 years.  I am using the crank to turn the engine over.  I've got a spark plug connected to the mag. laying on the exhaust manifold and get no spark.  From what I know about mags (which isn't much) I should be getting a spark when using the crank.  This is a Fairbanks-Morse mag.  Does anyone know of a mag repair person in the west central part of WI.Thanks!
Reply:Hello, central WI here. Mosinee machine does a lot of welder repair, but mostly newer stuff. There is a guy right close to him that does a lot with old tractors. I believe it's called Stroiney implement. PM me for more information if you wish.
Reply:Check the breaker points. Not uncommon for them to be crusted over after sitting for a very long time without running. Cleaning them with fine sandpaper typically does the trick.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110

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Reply:Similar, but, not exact,,i tinker with the old Gravely two wheel tractors,, on occasion.The #1 thing is the magneto not firing.If that ratty, mouse chewed wire shown in your pic touches ground anywhere,, NO SPARK!Remove the wire, completely, for now,, worry about the wire after you get spark.Next, with a Gravely, I simply remove the spark plug, and turn the engine over with a big electric drill,, until the magneto sparks.Simple use will many times clean the points enough to get it operating.I have no idea how hard your engine is to turn over,, you may have to get creative,, either a big electric motor, or gas engine, like 5HP,, and belt drive the engine to crank it over,, if you have a pulley on the engine.Whatever the case, the engine will crank much easier with the spark plug(s) removed.The spark plugs aren't doing any good in the engine, if there is no "SPARK"!!  Take them out.Good luck.
Reply:The RUN switch has to be in the open position to get a spark. When the switch is closed the spark is grounded. In other words, when the switch is in the ON position , the magnito is shorted and no spark. The switch has to be open in the OFF position to run. I know it sounds backwards but normally switches are used to turn something on in the ON position (closed contacts) but the kill switch on a mag is ON (closed contacts) to short the spark.  Also, theres insulators where that chewed up kill wire is that can become so dirty that it shorts the spark. Easiest test for switch polarity is to remove the chewed up wire and test.