73-20-04 CESSNA: Amendment 39-1726. Applies to Model R172E (T-41B) Serial Numbers R172-0001 through R172-0256) airplanes.
Compliance: Within 50 hours' time in service after the effective date of this AD, unless already accomplished.
To prevent complete loss of engine power when using the fuel boost pump, accomplish the following:
Modify the fuel boost pump electrical circuit by installing a new boost pump switch, electrical resistors, and placard in accordance with Cessna Service Letter No. SE73-24, dated August 24, 1973, and Service Kit SK172-43, or later FAA-approved revisions, or any equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region.
This amendment becomes effective October 3, 1973.