Service difficulty report · Coil

Difficulty date
August 20, 2009
Submitted
October 23, 2009
Operation
General aviation
Part
Coil
Part number
K3975
Condition
Worn
Location
Magneto
Component
Magneto · Slick
Component part number
4381
Stage of operation
IN
How discovered
9
Nature of condition
O
Precautionary procedure
K

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

(CAN) MAG WAS RECEIVED FOR 500 HOUR INSPECTION, NO DETAILS GIVEN. UPON DISASSEMBLY GREASE WAS FOUND ON THE DISTRIBUTOR AND ROTOR GEAR TEETH. THESE SHOULD NOT HAVE ANY GREASE ON THEM AS THEY ARE NYLON GEARS. WHEN THE DISTRIBUTOR BLOCK WAS REMOVED A WEAR RING WAS FOUND ON THE COIL TAB BECAUSE THE TAB HAD BEEN BENT UP ABOVE THE MAG FRAME PARTING SURFACE AND CONTACTED THE END OF THE DISTRIBUTOR GEAR SHAFT. WHEN THE COIL WAS TESTED FOR RESISTANCE THE SECONDARY WINDINGS WERE FOUND TO HAVE AN OPEN CIRCUIT CONDITION. UPON FURTHER EXAMINATION THE COIL WEDGES APPEAR TO HAVE BEEN REUSED (PRY MARKS UNDER THE WEDGE HEADS) INDICATING THAT THIS HAS BEEN A USED COIL INSTALLED IN THE MAG. SLICK REQUIRES REPLACEMENT OF THE INTERNAL MAG PARTS WITH NEW PARTS ONLY. THIS MAG HAS AN SIL REPAIR STICKER ON IT DATED 10/05/07, REF #14174. AN ESTIMATE TO REPAIR HAS BEEN SENT TO THE CUSTOMER. (TC# 20090820008)