TM-9-2350-277-20-2 Unit Maintenance Manual Volume 2 M113A3 M577A3 M1064A3 M1068A3 M58 Download
Page 177 of 790
TM 9-2350-277-20-2 PREVENTIVE MAINTENANCE CHECKS AND SERVICES (PMCS), INCLUDING LUBRICATION INSTRUCTIONS — Continued 0155 00 ITEM NO. INTERVAL MAN- HOUR ITEM TO BE CHECKED OR SERVICED C R E W M E M B E R PROCEDURE EQUIPMENT NOT READY/ AVAILABLE IF: c. The sound produced from a good spline drive coupling is muffled, and can be heard as the engine is cranking. The sound is muffled because the external spline on the spline drive ring is nylon coated. When the nylon coating, which is only 13 to 20 thousandths of an inch thick, on the spline drive ring is good, it will mate tightly with the engine’s internal spline teeth and produce a muffled sound. The sound produced from a worn-out spline drive coupling is a very distinct metallic clanking sound that can be easily heard as the engine is cranking. When the nylon coating on the spline drive ring is worn-out, it engages in a metal to metal backlashing with the flywheel’s internal spline teeth which are uncoated. This causes the metallic clanking sound. b Semi- Annual Transmission/ Engine Spline Drive (second a. The second type of inspection is the manual audio method. Metallic clanking sound is heard. WARNING Fuel cut-off control at driver’s position must be pulled all the way out to prevent engine from starting. Personnel could be injured or killed if engine starts during this PMCS check. b. Loosen the three wing nuts and clamps to remove the engine’s rear access panel from the crew compartment. This will access the engine’s variable drive assembly pulley. c. The pulley has three jacking bolt holes with 3/ 8" coarse thread. Hand tighten two 3/8" by 3" long bolts into the jacking holes. 0155 00-157 Change 3 check)