ITEM INTERVAL ITEM TO BE PROCEDURES CHECK FOR AND HAVE REPAIRED OR ADJUSTED EQUIPMENT IS NOT READY NO. B    D    A D    W   M    Q   S A INSPECTED AS NECESSARY AVAILABLE IF TM 55-1930-209-14&P-17 Table C-1.  Preventive Maintenance Checks and Services for Workboat, Lifesaving, and Firefighting Systems (Continued) B - Before D - Daily Q - Quarterly D - During W - Weekly S - Semiannually A - After M - Monthly A - Annually 3) Unscrew and remove spark plugs. 4) Spark plugs should be replaced if the Electrodes are electrodes are black or white or if black or white or if porcelain is cracked. porcelain is cracked. NOTE Spark plugs whose electrodes are tan in color need not be replaced. 5) If new spark plugs are required, use Champion RN-3 spark plugs. 6) Install spark plugs and torque tighten to 20 lb/ft. 7) Reinstall spark plug cables. 8) If the spark plugs were replaced because their electrodes were either black or white. 9) Remove the "OUT OF SERVICE" tag. r. Check the ignition timing annually or when starting is difficult.  Perform the pro- cedure as follows: 1) Shut down the pump and tag "OUT OF SERVICE." 2) Remove spark plug wires from spark plugs. 3) Remove retractable starter by remov- ing three hex head bolts. 4) Unscrew and remove three hex head bolts and remove starter pulley. 5) Twist fan belt out of the way. CAUTION When adjusting the stator assembly, take care not to damage the coil windings. C-38