TM 9-6115-646-14&P Table 4-1.  Unit Preventive Maintenance Checks and Services (PMCS) (cont). H-Hours of operation M - Monthly S-Semiannually (As Indicated) (100 hours) (500 hours) Interval Item Item to be Inspected. Procedures No. H M S 6 • V-Belts Inspect  for  worn,  frayed,  oil  soaked,  or  cracked belts.  Check adjustment.  Proper adjustment for fan belt is a deflection of 1/2 inch with application of  12-14  lb  pressure  midway  between  fan  and accessory drive pulley. 7 • Fuel Filters Replace filter elements after every 100 hours of operation. 8 300 Fuel Strainers Clean fuel strainer. 9 300 Lubricating Oil and Filters Change lubricating oil and filter.  (Refer to L.O.) 10 300 Breather and Breather Tube Inspect for damage.  Clean breather and tube at oil change interval. 11 AR Air Cleaner Clean air cleaner element whenever necessary as indicated by air filter condition indicator light. 12 • Taillights Replace  any  broken  or  cracked  lenses  or defective bulbs. 13 • Intervehicular Cable Check   for   cuts,   breaks,   frayed   wires,   or damaged plug. 14 • Lunette Check  security  of  mounting.    Inspect  ring  for excessive wear. 15 • Safety Chains Inspect for broken links or missing chain(s). 16 • Reflectors Replace   any   cracked,   broken,   or   missing reflectors. 17 • Data Plates and Markings Make sure data plates are legible and securely mounted.  Replace illegible data plates. 18 • Swivel Casters Inspect  swivel  caster  wheels  and  struts  for bent or broken parts. Change 1  4-10