TM 10-4610-232-12 Table 4-1.  Unit Preventive Maintenance Checks and Services Item No. Interval Item To Be Check Or Service Procedure Not Mission Capable If: 28. Annual Control Panel Check control panel pressure Correct activation cannot cannot switch actuation point. be obtained. 29. Annual Diesel Heaters a.  Notify DS maintenance to remove excess carbon from heater burner head. b.  Notify DS maintenance to check heater blower motor bushes and clean blower motor assemblies with compressed air. 30. 2,500 Hours Raw Water Pump Notify DS maintenance to replace Assembly mechanical seal in pump and inspect pump for internal wear. 31. 2,500 Hours High Pressure Notify DS maintenance to replace Pump Assembly valve disks and check valve seat for wear. 32. 2,500 Hours Flowmeter Notify DS maintenance to check Sending Units paddles and pins on the three units for damage, wear and ease of rotation. 33. 5,000 Hours High Pressure Notify DS maintenance to replace Pump Assembly plunger packing and inspect plungers for wear. 34. 5,000 Hours Cyclone Separator Notify DS maintenance to inspect Assembly separator lines for wear. 35. 10,000 Air Compressor Notify DS maintenance to replace Hours air compressor assembly high pressure air relief valve. 36. 10,000 Air System Notify DS maintenance to replace Hours air system low pressure relief valve. 37. 20,000 Raw Water Pump Notify DS maintenance to replace Hours Assembly motor bearings. 38. 20,000 Air Compressor Notify DS maintenance to replace Hours motor bearings. 39. 20,000 Distribution a.  Notify DS maintenance to replace Hours Pump Assembly mechanical seals in the pumps and Booster and inspect pumps for internal Pump wear. b.  Notify DS to replace motor bearings. 4-12  Change 2