TM-9-2350-311-20-1 Maintenance Manual for Volume 1 M109 Hull Download
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TM 9-2350-311-20-1 1-15 DIFFERENCES BETWEEN MODELS Differences between models exist (1) when comparing the M109A2 and M109A3 Howitzers; (2) when comparing one M109A3 to another M109A3 Howitzer and (3) when comparing the M109A2/M109A3 and M109A4/M109A5 Howitzers. 1-15.1 Hull Rear Doors The hull rear doors differ among the howitzers. Earlier versions have double doors and later versions have single doors. All M109A2 Howitzers have single doors (para 11 -12). 1-15.2 Personnel Heater Exhaust DefIector There is no personnel heater exhaust deflector on earlier howitzers. All later howitzers and all M109A2 Howitzers have the personnel heater exhaust deflectors mounted on the exhaust grille. 1-15.3 NATO Slave Start Receptacle At present, not all of the M109 Howitzers have NATO slave start receptacles. Also, the slave start receptacle location differs between the M109A2/M109A3 and M109A4/M109A5 Howitzers. The M109A2/M109A3 NATO slave start receptacle is located in the battery compartment. The M109A4/M 109A5 NATO slave start receptacle is located in the driver’s compartment (para 8-38). 1-15.4 Primary Fuel Filters The primary fuel filters are located in different areas of the engine compartment. Some earlier howitzers’ primary fuel filters are positioned near the engine vibration damper and the engine oil pan. The later howitzers’ primary fuel filters are positioned near the oil filters attached to the transmission (vehicle front) (para 6-6). 1-15.5 Travel Locks There are some travel lock differences involving the spring anchors. Differences are minor and are shown in paragraph 11-14. 1-15.6 Ventilated Face Piece System (VFPS) M109A4/M1 09A5 Howitzer hulls have a VFPS consisting of two air heaters, an air purifier, and required hoses. 1-15.7 Telephone Terminals The location of vehicle telephone terminals differ on M109A2/M109A3 and M109A4/M109A5 Howitzers. The M109A2/ M109A3 terminals are located on the hull rear bulkhead. M109A4/M109A5 terminals are located on the hull rear roof (exterior). 1-15.8 External Power Receptacle M109A4/M109A5 Howitzers have external power receptacles located on the rear hull bulkhead. 1-15.9 Alternator and Charging System M109A2/M109A3 Howitzers have 100-amp alternators/rectifiers. M1 09A4/M1 09A5 Howitzers have 180-amp alternators/rectifiers. The location for both configurations is the same. 1-14