78-20-09 GULFSTREAM AMERICAN CORPORATION (GAC) (FORMERLY GRUMMAN AMERICAN AVIATION CORPORATION (GAAC): Amendment 39-3309. Applies to Model GA-7 serial numbers GA7-001 through GA7-0039.
Compliance is required within the next 25 hours' time in service after the effective date of this AD, unless already accomplished.
To prevent a hazard to the airplane caused by excessive force required to move the fuel selector valve from one position to another position, accomplish the following:
(1) Remove the two original fuel selector valves, Gerdes Part Number A980-5, and install two new improved fuel selector valves, Gerdes Part Number A980-7, utilizing the procedures and precautions contained in GA-7 Maintenance Manual, Section 28-2-1, pages 202 and 204, Fuel Selector Valve Removal, and Fuel Selector Valve Installations.
(2) After the Gerdes Part Number A980-7 fuel selector valve installation has been completed in accordance with the above Maintenance Manual procedures, set each selector to ON, OFF, and CROSSFEED positions while observing each selector valve to ensure that the valve operates correctly, no fuel leakage occurs, and a positive detent is noted at each position selected on the valve.
(Gulfstream American Service Bulletin No. ME-10 dated August 16, 1978 applies to this same subject.)
This amendment becomes effective October 9, 1978.