87-04-01 PIPER: Amendment 39-5558. Applies to Model PA-46-310P (Serial Numbers 46-8408001 through 46-8608067, 4608001 through 4608018, 4608021, 4608023 and 4608025) airplanes certificated in any category. \n\n\tCompliance: Required within the next 25 hours time-in-service (TIS) after the effective date of this AD, unless already accomplished. \n\n\tTo prevent engine power loss, accomplish the following: \n\n\t(a)\tRemove the top and the lower left-hand engine cowl. \n\n\t(b)\tDetermine whether or not the alternate air valve linkage shown in Figure 1. has been installed on the left side of the engine air box. \n\n\t\t(1)\tIf the alternate air valve linkage shown in Figure 1. is not installed, install the Alternate Air Valve Modification Kit offered in Piper Service Letter 985 dated April 18, 1986, in accordance with the instructions contained within the kit, and verify proper operation in accordance with the instructions in paragraphs (b)(2)(i) through (b)(2)(vii) below. \n\n\t\t(2)\tIf the alternate air valve linkage shown in Figure 1. is installed, accomplish the following unless already accomplished in accordance with Piper Service Bulletin 852 dated November 14, 1986: \n\n\t\t\t(i)\tPosition the alternate air control (located inside the cockpit) approximately mid-way between the primary and the alternate position. \n\n\t\t\t(ii)\tRefer to Figure 1. and bend the stop tab so that the linkage is stopped 0.12 inch plus 0.060 minus 0.000 inch before center. This dimension is determined by measuring the perpendicular distance between a line through the centers of the cable lever and the valve lever hinge bolts and the center point of the center hinge bolt. \n\n\t\t\t(iii)\tPosition the alternate air control (located inside the cockpit) in the primary (up position). Insure that the control is in the gate that prevents it from springing downward. \n\n\t\t\t(iv)\tAdjust the cable housing in the cable clamp so that the cable pushes the linkage against the stop tab. \n\n\t\t\t(v)\tResecure the cable clamp as necessary. \n\n\t\t\t(vi)\tOperate the alternate air control (located inside the cockpit) between the primary and the alternate air positions. \n\n\t\t\t(vii)\tCheck for normal operation and that the linkage does not go over-center when the alternate air control (located inside the cockpit) is in the "primary position." \n\n\t(c)\tReinstall the lower left-hand and the top engine cowl. \n\n\t(d)\tAircraft may be flown in accordance with FAR 21.197 to a location where this AD may be accomplished. \n\n\t(e)\tAn equivalent means of compliance with the requirements of this AD may be used if approved by the Manager, Atlanta Aircraft Certification Office, 1669 Phoenix Parkway, Suite 210, Atlanta, Georgia 30349. \n\n\tAll persons affected by this directive may obtain copies of the document(s) referred to herein upon request to Piper Aircraft Corporation, 2926 Piper Drive, Vero Beach, Florida 30960; or may examine the document(s) at the FAA, Office of the Regional Counsel, Room 1558, 601 East 12thStreet, Kansas City, Missouri 64106. \n\n\tThis amendment becomes effective on February 24, 1987. \n\n\n\n\nFIGURE 1\nAD 87-04-01