Cessna 340/340A 1971–2009 Installation Instruction and Service Manual OEM (P/N 34-010-61M)

• 21-page PDF set for the Cessna 340/340A: Keith Products Installation Instruction and Service Manual, Report No. 34-010-61M (12 pages); AAIB Bulletin 1/2012 accident report EW/G2010/07/19 (7 pages); and RAM Aircraft performance sheet SM038A12 (2 pages).
• Covers installation of the Keith 34-010-61 R134a air-conditioning kit, including refrigerant plumbing and wiring routes, pressure-bulkhead penetrations, the compressor/motor pallet, condenser, condenser fan, inlet deflector, and aft overhead evaporator assembly.
• Details the Equipment Package and Evaporator Package, with maintenance coverage for the compressor drive belt, mounting security, refrigerant sight gauge, evaporator cleaning, and pressurized-aircraft condensate drain valve.
• Provides component-replacement repair limits, belt inspection and adjustment data, evacuation and charging references, and the operating checks required after installation.
• Includes a Vapor Cycle Schematic, a right-main-landing-gear downlock mechanism schematic, component-location and fracture photographs, and a three-view Cessna 340/A dimensions drawing.
• Adds a case-specific landing-gear investigation for Cessna 340A N346DW plus RAM Series IV and Series VI performance comparisons for stock and modified Cessna 340/A configurations.

Keith R134a Installation Coverage

Keith Report No. 34-010-61M is the core factory document in this set. Issued September 1, 1995, it covers the Cessna 340 and 340A installation rather than a generic vapor-cycle system. The work begins with removal of the left-side seating, switch and circuit-breaker console, and forward baggage-compartment floors to gain access for the alteration. It then addresses the airframe-specific routing of hoses, wiring, and the condensate drain through the forward and aft pressure bulkheads.

The compressor and electric drive motor mount on a pallet supported at defined fuselage stations. Separate sections cover the condenser, floor-panel clearance, condenser fan, ducting, skin doubler, inlet deflector, screen, and negative scoop. The evaporator package mounts on the aft overhead centerline with its blower motor, expansion valve, drain hose, cover, and forward distribution duct. Because this repair and installation scope includes skin cutouts, structural attachments, pressure-boundary penetrations, aircraft wiring, and refrigerant plumbing, the publication is suited to experienced aircraft maintenance personnel already familiar with pressurized-airframe alteration and vapor-cycle A/C systems.

The manual calls for adequate clearance between the condenser fan and compressor pallet and for sealed pressure grommets at the hose penetrations. Incorrect layout can leave interference or an improperly sealed pressure boundary. It also warns against restarting the system immediately after shutdown; insufficient time for compressor head pressure to bleed down can impose an abnormal starting load.

Service Content and Important Limits

The service section explains refrigerant flow through the compressor, condenser, receiver dryer, expansion valve, and evaporator. Its illustrated Vapor Cycle Schematic distinguishes high- and low-pressure gas and liquid paths and shows the relationship between outside airflow, cabin airflow, and condensate drainage.

Maintenance coverage includes component cleaning, compressor-belt tension and post-installation retension, 100-hour checks of mounts and refrigerant level, evaporator debris removal, and operation of the electrically controlled condensate drain valve used on pressurized aircraft. The humidity guidance explains why an undrained evaporator pan can spill water into the cabin. Repair coverage is expressly limited to component replacement; this is not an overhaul or detailed fault-isolation manual.

Three required publications are identified but are not included in the PDF set: General Arrangement and Installation Drawing 34-010, Compressor/Condenser Installation Drawing 34-050, and Air Conditioning Service Manual TR-134. Report 34-010-61M directs the installer to TR-134 and the charging-equipment instructions for evacuation, charging, and testing. It does not provide a refrigerant capacity chart, complete wiring schematic, torque table, pressure-switch calibration procedure, O-ring replacement procedure, or receiver-dryer acceptance criteria.

Landing-Gear Case Study and RAM Data

The AAIB extract examines the 2011 right-main-landing-gear collapse of a 1979 Cessna 340A, N346DW, powered by TSIO-520-NB engines. It documents the downlock link, bellcrank, side brace, microswitch, adjusting screw, and pivot-bolt damage, then reviews the preceding maintenance, Cessna rigging requirements, metallurgical findings, and probable failure sequence. The investigation did not positively identify the initiating cause, so this seven-page report should be read as a single-event technical case study, not as substitute repair data for the full landing-gear system.

RAM document SM038A12 compares the stock Cessna 340/A with RAM 325 hp Series IV and 335 hp Series VI configurations. Its table covers engine designation, TBO, fuel, takeoff acceleration, climb and cruise performance, and operating-weight figures. A separate three-view drawing supplies overall aircraft dimensions. These two pages are performance-reference material and do not replace the applicable Pilot's Operating Handbook or FAA-approved Flight Manual Supplements for a specific airplane.