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Piston Pin Replacement

  1. Piston pin is interference fit in connecting rod. To remove piston pin use suitable tool (18G 1002) to avoid crushing or distorting piston. Hold hexagon body of tool in vise with cutout up.
  2. Screw large nut back until flush with end of center screw. Push screw and nut forward until nut contacts thrust race. Slide parallel sleeve, short length diameter first, onto center screw, up to its shoulder.
  3. Place piston assembly on center screw and attach remove/replacer bushing, longest diameter portion toward piston. Screw stop nut onto center screw and adjust until there is about 0.031" (0.794 mm) end play in whole assembly.
  4. Lock stop nut securely in position with lock screw and check that curved face of body is clean. Slide piston assembly into position against curved face. Check that piston rings are over cut-out in tool body.
  5. Screw large nut up to thrust race and hold lock screw (not stop not) with a wrench. Turn large nut until pin is pulled out of piston.
  6. To install pin, remove large nut of tool and pull center screw out a few inches. Slide parallel sleeve, longest length diameter part first, onto center screw up to its shoulder.
  7. Place piston on connecting rod small end up to undercut. Smear pin with thin oil and slide it over center screw and into piston bore up to face of connecting rod. Slide remover/replacer bushing, short spigot toward pin, onto center screw.
  8. Screw stop nut onto center screw and adjust until there is approximately 0.031" (0.794 mm) end play. Lock nut securely in position with lock screw. Check that curved face of body is clean and slide piston into position against curved face. Check that piston rings are over cut-out in tool body.
  9. Screw large nut onto center screw until it contacts thrust race. Using a torque wrench set to 16 ft.lbs. (2.2 mkg), and holding lock screw with wrench, turn large nut to pull pin until flange of remover/replacer bushing is 0.031" (0.794 mm) from piston skirt.
    NOTE: It is important that care is taken to prevent flange from contacting piston.
  10. If torque wrench reading has not reached 16 ft.lbs. (2.2 mkg) during the pull, fit of pin to connecting rod is not correct and pin must be replaced. Make sure to keep large nut and center screw of tool.
  11. Check assembly and make sure that piston pivots freely on pin and is free to slide sideways. If assembly is satisfactory, reinstall in engine.
    CRANKSHAFT MAIN & CONNECTING ROD BEARINGS

    Engine MAIN BEARINGS CONNECTING ROD BEARINGS
    Journal Diam. In. (mm) Clearance In. (mm) Thrust Bearing Crankshaft End Play In. (mm) Journal Diam. In. (mm) Clearance In. (mm) Side Play In. (mm)
    1275 cc 2.0005-2.0010 .0010-.0027 Center .002-.003 1.6254-1.6259 .0010-.0025 .006-.010
      (50.813-50.825) (.025-.069)   (.051-.076) (41.285-41.297) (.025-.064) (.152-.254)
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