Lycoming Organizational, DS and GS Maintenance Manual Aircraft Reciprocating Engine Models 0-435-23C, FSN 2810-919-0188 and 0-435-25A, FSN 2810-949-8268. TM 55-2810-221-24, dated 19 June 1971. Contains 13 chapters: Introduction, Special Tools Test Equipment and Consumable Materials, Preparation for Service Storage and Engine Handling, Troubleshooting, Accessories Servicing, Engine Disassembly, Cleaning Inspection and Repair, Assemblies of Subassemblies, Final Engine Test, Torque and Dimensional Limits, Special Instructions, and Overhaul Interval and Retirement Schedule. Also contains 4 Appendices: References, Maintenance Allocation Chart, Illustrated Field Manufacture Items List, and Repair Parts and Special Tool List. Manual is a copy.