TM   5-6115-545-12 TO-35C2-3-444-1 NAVFAC   P-8-626-12 TM-00038G-12 3.78  Replacement  of  Suppression  Components,  (Cont) d.  Main  AC  Contactor  Three  RFI  suppression capacitors C3, C4 and C5 are connected between terminals A2, B2, and C2 respectively, of the main ac contractor CB2 and  ground.  Replace  suppression  capacitors  as  shown  in  A of figure 3–11. e.    Day  Tank Solenoid Valve. Diode suppressors CR27 are provided at the connector of the day tank solenoid valve. Replace diode suppressors as shown in B of figure 3-11. 3-79.  Testing of  Radio  Interference  Suppression Components. Test  the  capacitors  for  leaks  and  shorts  using  a  multimeter  or other capacitor tester. Replace defective capacitors. If test equipment  is  not  available  and  interference  is  indicated, isolate the cause of interference by the trial and error method of  re-  placing  each  component  in  turn  until  the  cause  of interference  is  located  and  eliminated. Figure 3-10. Lockwire of Fuel Injector Pump for Class 2 Operation Section VIII. ORGANIZATIONAL MAINTENANCE 3-80.  General maintain the engine generator set at the organizational level. Instructions are provided in sections IX through XLIV for Where essential, sections are arranged in the most logical the information and guidance of responsible personnel to order  of  disassembly  of  equipment. Section IX. BATTERIES, AND RELATED PARTS 3-81.  General. This section contains information on the batteries, battery  tray  and  slave  receptacles  of  the  engine  generator  set. Two 12-volt 100 ampere, lead acid type batteries are mounted side by side on a battery tray. The batteries are electrically connected in series to supply 24 Vdc for starting the engine generator set. There is a slave receptacle electrically connected in parallel with the batteries. The receptacle  facilitates  external  connection  with  the  batteries, in order to supply or receive an auxiliary source of electrical power. A source of 24 Vdc electrical power is therefore available for other development. Normally, the engine generator set should be operating so as not to run down the batteries  when  supplying  this  source  of  dc  power. 3-82.  Batteries. a. Replacement.  To replace one or both batteries, see figure 3-4 and proceed as follows: (1) Remove screw (lA), nut (lB) and clamp (lC). Disconnect battery negative cable (1) positive cable (2) and jumper cable (3) from storage batteries (4) (2) Remove two nuts (5) and lockwashers (6), which secure battery retainer (7) to studs (8), and remove storage  batteries  (4). (3) Install new storage battery in reverse order of removal. b. Battery  Testing. NOTE Failure to perform this task prior to adding distilled water will result in an erroneous  reading. Battery  hydrometer  readings  should  be  tested  on  all cells monthly. Always test a battery for a degree of charge before adding water. The specific gravity between the cells should be within .05. A dangerously low point of charge indicated by a hydrometer reading of 1.150 or less will permit the battery to freeze at a temperature of 5° F. A specific gravity of 1.250 will permit the battery to withstand temperatures  as  low  as  -65°F  without  freezing.  An acceptable  hydrometer  reading  of  1.210-1.220  at  80°F  will be obtained from a fully charged battery (2.0-2.2 volts dc per cell). Battery reading of less than 1.200 or cell variance of .05 or greater will be replaced if attempts to restore the battery fail.  Compare  specific  gravity  readings  with  previous readings  for  cell  deterioration. NOTE The  6TN  and  6TL  batteries  can  be  mixed  or  matched. However, maintenance–free batteries cannot be mixed or matched with military batteries. The 6TN and or the 6TL batteries will perform properly in hot weather as long as electrolyte  levels  are  carefully  monitored.  If  the  electrolyte expands and causes the level to rise, some fluid must be removed.  If  the  level  becomes  too  low  due  to  evaporation, distilled water may be used to obtain the proper level. A good grade of drinking water (excluding mineral waters) may be used if distilled water is not available. Electrolyte   (NSNs   6810-00-249-9354   and 6810-00-843-1640) have a specific gravity of 1.280 and should be used in these batteries. Do NOT adjust the electrolyte  in  wet  batteries  to  a  lower  specific  gravity. Change 17 3-29