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Engine Disassembly

NOTE: To simplify engine disassembly, manufacturer recommends use of a special engine stand (49 0839 000 or 49 0107 680A) and special hanger (49 1114 005) for supporting the front housing. See Fig 1. Also note that this front housing support may be used on previous engines (where rear housing support units were previously used).
  1. Remove oil hose support bracket from front housing, then mount engine on stand and front housing support. Remove engine hanger bracket from front cover. Disconnect vacuum hoses, air hoses and wiring. Remove deceleration valve and vacuum control valve. Remove air pump and drive belt. Remove alternator and belt.
  2. Disconnect metering oil pump connecting rod and oil tubes. Remove inlet manifold and carburetor as an assembly. Remove manifold gasket and "O" rings. Remove thermal reactor (exhaust manifold), distributor, engine mounts and oil filter assembly. Remove eccentric shaft pulley for compressor.
    NOTE: Further disassembly requires attachment of braking tool (49 1881 060) to flywheel of manual transmission equipped vehicles or stopping tool (49 1881 055) to counterweight of automatic transmission equipped vehicles.
    Fig 1: Engine Stand & Hanger Support
    G09334499Courtesy of MAZDA MOTORS CORP.
  3. Remove water pump and gasket. Invert engine on stand and remove oil pan, gasket and strainer with gasket.
    NOTE: When removing oil pan, pry upward using two screwdrivers, one on each side of oil pan and just in front of tapered corners on flywheel end.
  4. Mark front and rear housings for installation in their original positions. Return engine to upright position. Unscrew eccentric shaft pulley bolt and remove pulley.
    Fig 2: Removing Sprocket & Chain from Engine
    G09334500Courtesy of MAZDA MOTORS CORP.
  5. Turn engine so that front end is up. Remove front cover with gasket. Remove "O" ring from oil passage on front housing. Slide distributor drive gear off shaft. Remove chain adjuster. Remove oil pump sprocket lock washer and nut. Slide oil pump sprocket and eccentric shaft sprocket and drive chain off shafts simultaneously. See Fig 2. Remove keys from shafts. Slide balance weight, thrust washer and needle bearing off shaft.
  6. Remove bearing housing, needle bearing, spacer and thrust plate from shaft. Remove oil pump. Return engine to upright position.
  7. Remove clutch cover assembly and clutch disc. Straighten tab on lock washer and remove flywheel nut using special tool (49 0820 035). Remove the flywheel using puller (49 0823 300A or 49 0839 305A).
  8. If equipped with automatic transmission, remove counterweight. To do so, remove drive plate. Straighten tab of lock washer and remove counterweight nut using special tool (49 0820 035). Remove counterweight, using puller (49 0839 305A).
    Fig 3: Loosening Sequence of Tension Bolts
    G09334501Courtesy of MAZDA MOTORS CORP.
  9. Turn rear of engine upward. Loosen tension bolts in sequence shown in Fig 3, doing so in two or three steps. Remove bolts and lift rear housing off shaft. Remove any seals stuck to rotor sliding surface of rear housing, and replace them in original positions. Remove and discard two sealing rubbers and two "O" rings from rear side of rear rotor housing.
  10. Attach dowel puller (49 0813 215A). Pull tubular dowels (See Fig 4) from rear rotor housing. Hold housing with hand to prevent it from turning or pulling upward. Lift rear rotor housing away from rotor, being careful not to drop apex seals off rear rotor. Remove and discard two sealing rubbers and two "O" rings from front side of rear rotor housing.
    Fig 4: Extracting Tubular Dowels from Engine
    G09334502Courtesy of MAZDA MOTORS CORP.
  11. Remove side pieces, apex seals and springs from rear rotor and store in order for reassembly. Remove all corner seals, corner seal springs, side seals and side seal springs and store in order for later reassembly.
  12. Remove rear rotor from eccentric shaft and place it upside down on a clean sheet of cloth. Remove seals and springs from remaining side of rear rotor and store in order for reassembly.
    Fig 5: Prying Oil Seal from Rotor
    G09334503Courtesy of MAZDA MOTORS CORP.
  13. Mark each rotor as to front or rear. Remove oil seals from rear rotor using suitable prying tool (49 0813 225), Fig 5, being careful not to damage oil seal lip.
    NOTE: Do not exert strong force at any one point in removing seal. Mark rear oil seal springs of each rotor to aid in repositioning them upon reassembly.
  14. Holding intermediate housing down by hand, pull tubular dowel from intermediate housing, using dowel puller (49 0813 215A). See Fig 4. Lift intermediate housing from shaft. To do so, hold housing up off front housing, while helper pushes upward on eccentric shaft. Lift out eccentric shaft.
  15. Repeat procedures 10)  through 14)  to remove front rotor housing and rotor assembly.
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