TM 55-1930-209-14&P-19 Table 7-2.  Preventive Maintenance Checks and Services for Compressed Air System (Continued) B - Before D - Daily Q -  Quarterly D - During W - Weekly S -  Semiannually A - After M - Monthly A -  Annually INTERVAL ITEM PROCEDURES EQUIPMENT ITEM TO BE CHECK FOR AND HAVE IS NOT READY/ NO. INSPECTED REPAIRED OR ADJUSTED AVAILABLE IF B   D   A   D  W  M   Q   S   A AS NECESSARY NOTE Semiannually,   replace   both   air   filters with new assemblies (FSCM 16327, P/N Z66A, muffler assembly, intake). g. Check Barges 2 and 3 pulley clamp bolts and setscrews for tightness and drive belts for correct tension, condition, and alignment as follows: 1) Drivebelt replacement: (a) Shut down air compressor system. (b) Redtag power panel 1 circuit breaker 3P5 indicating, "WARNING - DO NOT ACTIVATE. REPAIRS BEING MADE." (c) Remove belt guard from compres- sor by unscrewing three bolts (two have spinlock nuts).  Place bolts, washers, and nuts with guard and place where it will not be damaged. (d) With two V-belts exposed, check appearance for frayed, worn, or extra hard and shiny edges or breaks in underneath side of belts. If belts show these signs, belts must be replaced in pairs (FSCM 16327, P/N 3X645). (e) Loosen four belts holding electric motor to base plate, slide motor towards compressor until belts can be slipped off pulleys.  Discard old belts. (f) With belts off, and using a torque wrench, check tightness of bolt holding compressor pulley on compressor shaft.  Torque to 500 in-lb.  With normal wrench, check tightness of setscrew holding puley on electric motor shaft. Setscrew must be wrench tight. 7-21