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• MJK Ed A,B,C Service Manual

MJK Ed A,B,C Service Manual

The MJK to the best of our knowledge was made exclusively for the Caterpillar Tractor Co. for their diesel starting pony motors.  They were and still are an excellent, hot magneto.  They came in a multitude of configurations including base mount, flange mount, horizontal mount, gear drive, impulse coupled, clockwise, counterclockwise, and fired at 180 or 90 degrees. If yours is gear driven on a D2 or D4 be aware of loose engine bearings. If the engine bearings have excessive wear it will break the magneto armature driveshaft every time. If you get a cat with a broken magneto drive gear and driveshaft this likely what happened and will happen again in short order.   Applications with combinations of any and all of the above aforementioned will be found. Some parts are specific to the particular application. Here is some factory service info to keep yours alive and well. Parts info to follow.