Service difficulty report · Points · Cessna 170B

Difficulty date
August 23, 2026
Submitted
August 24, 2026
Operation
General aviation
Aircraft
N2711C
Make and model
Cessna 170B
Aircraft serial
26255
Aircraft time
4,612 hours
Engine
Cont IO360C
Engine time
58 hours
Propeller
Mcauly 2A34C203
Part
Points
Part number
A13081
Condition
Defective
Location
Magneto
Part time
58 hours
Component
Magneto · Kelly · E6314
Component part number
ES6314
Stage of operation
TX
How discovered
V
Nature of condition
R
Precautionary procedure
D

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

What was found

THE ENGINE INTERMITTENTLY RAN ROUGH ON THE RIGHT MAG CHECK AND WOULD OCCASIONALLY COMPLETELY CUT OUT BUT THE EGT'S DIDN'T POINT TO ANY PARTICULAR CYLINDER. THE P LEADS AND IGNITION SWITCH TESTED GOOD. I REMOVED AND DISASSEMBLED THE RIGHT MAG. I FOUND THE RIVET ATTACHING THE CONTACTOR ON THE FIXED SIDE OF THE POINTS TO BE LOOSE AND ALLOWING THE CONTACTOR TO MOVE ENOUGH TO DRAMATICALLY CHANGE THE E GAP AND AT TIMES REDUCE IT TO ZERO CAUSING THE MAG TO EFFECTIVELY CUT OUT. I ALSO FOUND THE SPRING-LOADED CARBON CONTACTOR ON THE DISTRIBUTOR GEAR GUMMED UP WITH GREASE AND NOT MOVING FREELY. IT'S CONTACT POINT ON THE COIL WAS ALSO GUMMED UP WITH GREASE. THESE TWO THINGS LIKELY CAUSED A POOR CONNECTION BETWEEN THE DISTRIBUTOR GEAR AND THE COIL. THIS MAG WAS INSTALLED NEW ON 3/3/2025 AND IT HAS 58.2 HOURS TOTAL TIME ON IT. THE MANUFACTURE DATE STAMPED ON THE POINTS IS OCT 11, 2021.

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