AD 73-07-07

73-07-07 CESSNA: Amdt. 39-1617. Applies to all Models 310 and 320 series airplanes and Serial Numbers, except Models 310, 310A, 310B and 310Q (Serial Numbers 310Q0710 and up).

Compliance: Required as indicted, unless already accomplished.

To determine condition of fuel lines, electrical wiring, and to detect loose fittings and attachments, to reduce possible collection of flammable fluids and to eliminate possible ignition sources within the leading edges of the wings, within the next 25 hours' time in service after the effective date of this AD, accomplish the following in accordance with Cessna Multi-engine Service Letter ME73-5 dated March 16, 1973, and Cessna Service Kit SK310-90 dated March 7, 1973, or later FAA approved revisions or any other method approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region:

1) Inspect the fuel lines and electrical harnesses in the wing leading edge for corrosion, chafing, looseness, or other unserviceable conditions. Procedures for this inspection are contained in Cessna Service Kit SK 310-90.

2) Prior to further flight replace and/or repair any unserviceable parts or conditions found as result of the above inspection.

3) Install leading edge drainage and sealant provisions in the wings in accordance with Paragraph B of Cessna Service Kit SK 310-90.

4) Remove, relocate and reinstall the auxiliary fuel boost pump resistor and relay in accordance with Paragraphs C and D of Cessna Service Kit SK 310-90.

a) On those airplanes in which P/N 0850404-1 boost pump relay is installed, relocate this relay to wing trailing edge per Cessna Service Kit SK 310-90. (This relay is no longer eligible for installation in the wing leading edge.

b) P/N FC 215-136 boost pump relay already installed in the wing leading edge is acceptable and as an alternative to Paragraph a), P/N 0850404-1 boost pump relay may be replaced with P/N FC 215-136 boost pump relay installed in the present wing leading edge location.

c) On all airplanes relocate the boost pump resistor in accordance with Cessna Service Kit SK 310-90.

5) Place amended checklist entitled "Aircraft Fire Procedures Checklist" in the cockpit. This checklist is supplied with Cessna Service Kit SK 310-90.

This amendment becomes effective April 6, 1973.