CESSNA 172C manuals

This Service Bulletin SB-12, issued by McFarlane Aviation on December 12, 2023, addresses a critical safety issue concerning the outlet fitting of the MC0513120 series Fuel Selector Valves used in various Cessna aircraft, including the Cessna 172C. The bulletin highlights a potential failure condition that can occur if these valves are overhauled or reassembled with excessive torque applied to the outlet fitting. The bulletin mandates compliance for all affected valves, particularly those released before November 1, 2023, and outlines specific procedures for inspection, replacement, and documentation. It is essential for operators and maintenance personnel to follow the instructions to ensure safety and compliance with aviation regulations.

• Affected models include Cessna 170, 172, 175, and 177 series aircraft.
• Mandatory compliance for all MC0513120 series valves released before November 1, 2023.
• Torque specifications for the outlet fitting are 13-14 ft-lbs (156-168 in-lbs).
• Replacement of the outlet fitting and O-ring is required within 10 hours of operation or 3 months for valves with outlet port removal history.
• McFarlane will provide replacement parts free of charge to affected customers.