What was found
OWNER COMPLAINED OF A 'DEAD' LT MAGNETO. CHECKED TIMING AND FOUND POINTS OPENING PROPERLY. REMOVED MAGNETO AND DISASSEMBLED. FOUND INSIDE OF MAGNETO CORRODED AND COIL GROUND LEAD BROKEN. SUSPECT LEAD BROKE DUE TO THE CORROSION. SLICK SB1-88 REFERS TO INSPECTING MAGNETOS EVERY 100 HRS FOR MOISTURE CONTAMINATION. THIS WAS DONE ON THIS AIRCRAFT WITHIN 130 HRS. THIS IS A VERY IMPORTANT BULLETIN BASED ON THE FACT THAT THESE MAGNETOS ARE PRESSURIZED AND WILL TEND TO HOLD MOISTURE. SUBMITTER RECOMMENDS MAKING THIS A MANDATORY INSPECTION.