TM 5-4940-228-14 NOTE crankshaft (49), lift key (29) from crankshaft (49). You  should  follow  disassembly  pro- cedure only enough to get to damaged parts.  For  example,  if  valves  require servicing,  follow  procedure  until valves are removed. a. Remove pulsation tank (4) by unscrewing four bolts (3). b. Both  heads  (15)  can  now  be  removed  by  un- screwing  four  short  bolts  (13)  and  two  long  bolts (10)  from  each  side.  Washer  (11)  will  be  removed with  long  bolt  (10)  (Fig.  9-l). c. Both  heads  (15)  can  be  further  disassembled as follows: (1) Remove three screws (5) which allow you to take off filter retainer (6), outer filter (7), inner filter (8) and screen (9). (2) (Fig.  9-2)  Remove  five  bolts  (12a),  lift  off cover  (12  b),  remove  gasket  (12c)  and  lift  off  body (12d). (3) Push  both  pistons  (12e)  from  body  (12d). Remove  four  O-Rings  (12f).  Both  pins  (12g)  and both springs (12h) are loose and can be lifted out of head. d. (Fig. 9-1) Lift off gasket (16), valve assembly (17) and gasket (18). e. Both valve assemblies (17) can be further dis- assembled as follows: (1) Tap out two roll pins (17d) which hold the assembly together. (2) Top plate (17a) can now be disassembled by unscrewing four screws (17b) and removing two intake valves (17c). (3) Bottom plate (17g) can be disassembled by removing four screws (17h) and removing two dis- charge valves (17i). f. (Fig.  9-1)  Remove  cylinders  (21)  by  removing four each nuts (19) and washers (20). Lift off cylin- der (21) and gasket (22). g. Remove  four  pistons  (25)  by  removing  two pieces of lock wire (23) from each piston (25). Hold bottom part of piston (25) while removing two bolts (24) so parts do not fall into crankcase (54). h. (Fig.  9-4)  To  disassemble  piston  (25)  remove two  piston  pin  plugs  (25a),  push  piston  pin  (25b) thru piston (25g) and remove four rings (25c). i. (Fig.  9-1)  Remove  pulley  (28)  by  unscrewing two bolts (27) from two nuts (26). Slide pulley from j. Pull dipstick (26) from crankcase, O-Ring (39) can now be removed. h. Remove plug (34), unscrew coupling (35), un- screw  nipple  (36)  and  unscrew  elbow  (29)  from crankcase (54). l. Remove  two  breather  caps  (30),  two  springs (31), two valves (32), and two seats (33) from front carrier  (45).  Remove  five  bolts  (40)  and  pull  rear carrier  (41)  from  crankcase  (54).  Slide  crankshaft (46) out of crankcase (54). m. Remove  front  carrier  (41)  by  removing  five bolts (44). Gasket (46), oil seal (43) bearing cup (47) and bearing cone (48) can now be removed. 9-4. Cleaning and Inspection. Clean  all  parts  with  a  petroleum  based  solvent such  as  kerosene  or  diesel  fuel.  Inspect  parts  for damage or excessive wear. The following is a list of tolerances: Crankshaft journals . . . . . . . . . 1.500-1.495 in . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (3.810-3.797  cm) Connecting rod Crankshaft end . . . . . . . . . . . . . . . . 1.5018-1.5025 in . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (3.814-3.816  cm) Piston pin end . . . . . . . . . . . . . . . . . . 0.626-0.630 in . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (1.590-1.600  cm) Cylinder bore . . . . . . . . . . . . . . . . . . . . . . 2.625-2.630 in . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (6.667-6.680  cm) Piston pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.625-0.622 in . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (1.587-1.580  cm) Piston pin hole . . . . . . . . . . . . . . . . . . . 0.625-0.630 in . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (1.587-1.600  cm) Piston diameter . . . . . . . . . . . . . . . . . 2.619-2.615 in . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (6.652-6.642  cm) 9-5. Reassembly. a. (Fig. 9-1) Assemble two seats (33), two valves (32),  two  springs  (31)  and  two  breather  cups  (30) into rear carrier (41). Press bearing cup (47) and oil seal (43) into rear carrier (41). Using a new gasket (42)  and  five  bolts  (40),  attach  rear  carrier  (41)  to crankcase (51). b.  Install  a  bearing  cone  (48)  on  each  end  of crankshaft  (49).  Slide  crankshaft  (49)  thru  crank- case (51) (slotted shaft end first) and thru rear car- rier (41). Hold crankshaft centered while installing bearing cup (47), gasket (46) and front carrier (45). Screw in five bolts (44). Torque five bolts (40) and five bolts (44) to 225 in Ibs (40,185 gr cm). 9-3