TM 55-1930-209-14&P-2 Table C-1.  Preventive Maintenance Checks and Services for Seawater System (Continued) B - Before D - During A - After D - Daily W - Weekly M - Monthly Q - Quarterly S - Semiannually A - Annually ITEM PROCEDURES EQUIPMENT ITEM INTERVAL 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   Be sure O-rings on cover rest in O-ring damaged machined grooves before tighten- or missing ing yoke screw securely Do not overtighten. c.  Lubricate seawater pump motors and fit- tings, if necessary, with grease as speci- fied In manufacturer's manual d.  Be alert for unusual equipment noises, smells or overheating that might indicate pending equipment or system malfunc- tion 4     Seawater Pumps a.  When using seawater pumps 1 and 2 Class III leaks (void 2 starboard). 1)   Check seawater system components for normal operation and for leaks 2)   Inspect mounting bolts 3)   Regularly monitor seawater strainer input and output pressure gauges for:   A pressure difference of 2-4 Hg between the pressure gauges is normal   If the pressure difference reaches 8 Hg, turn handle on strainer to route seawater flew through clean strainer basket.   Remove and clean dirty strainer basket b.  Check gauges sand tubing for cracks or Class Ill leaks leakage 5     Seawater Filters a.  Drain seawater filters as follows: NOTE Drain only filter(s) In active use.  If only one ROWPU system Is In use with Just one seawater pump, then drain only filter(s) In use. Clean Water Operations Drain filter 15 seconds every 8 hours C-6