GM Service Manual Online
For 1990-2009 cars only

Press-Fit Piston Pin

Tools Required

J 24086-C Piston Pin Remover/Installer Set


    Object Number: 533475  Size: SH

    Important: 

       • Disassembly of the piston, press-fit design piston pin, and connecting rod may create scoring or damage to the piston pin and piston pin bore. If the piston, pin, and connecting rod have been disassembled, replace the components as an assembly.
       • If reusing the piston and connecting rod assembly, install the assembly to the original cylinder and corresponding crankshaft journal.
       • The assembly procedure, as shown, is to be used for diagnostic purposes only.

  1. Install fork insert J 24086-920 into J 24086-10 .

  2. Object Number: 1366369  Size: SH

    Caution: Avoid contact with HOT components. Wear safety glasses and protective gloves to avoid personal injury.

    Notice: Applying excessive heat to the connecting rod may damage or distort the rod. Rod temperature SHOULD NOT exceed 315°C (600°F). At this temperature the end of the connecting rod will turn a straw color upon visual inspection.

  3. Use a torch and apply MILD heat to the pin end of the connecting rod. Mild heating of the connecting rod will ease in piston and pin assembly.
  4. Identify the positioning tab (1) or flat flange (3) of the connecting rod. When properly assembled, the positioning tab or flat flange of the rod and the mark (2) on the top of the piston should both be facing the front of the engine.

  5. Object Number: 533488  Size: SH
  6. Assemble the piston, the connecting rod, and the J 24086-16A.

  7. Object Number: 533486  Size: SH
  8. Adjust the J 24086-9 to I 8.

  9. Object Number: 533483  Size: SH
  10. Install the piston, connecting rod, piston pin, and J 24086-16A to the J 24086-10 .

  11. Object Number: 1366357  Size: SH

    Notice: After the installer hub bottoms on the support assembly, do not exceed 35 000 kPa (5,000 psi) pressure, this could cause damage to the tool.

  12. Insert J 24086-9 through J 24086-10 and to the piston pin.
  13. Press J 24086-9 until the installer bottoms on the J 24086-10 .
  14. Inspect the piston (1), pin (3), and connecting rod (2) for proper assembly.
  15. When properly installed, the piston pin (3) should be centered in the connecting rod (2).


    Object Number: 1336810  Size: SH
  16. Identify the compression and oil control rings for proper installation. The upper compression ring can be identified by a paint mark (3) located 180 degrees from the end gap. The lower compression ring can be identified by a paint mark (3) located 90 degrees from the end gap. Both rings should be installed with the orientation marks (1, 2) facing the top of the piston. If no dimple or mark can be found on the top compression ring, it may be installed in either direction.

  17. Object Number: 490763  Size: SH

    Important: When installing piston rings, use a ring expander plier type tool. Do not roll the rings into the grooves of the piston. Use caution and care to expand the rings only slightly larger than the outside diameter (OD) of the piston.

  18. Using piston ring pliers, install the piston rings onto the piston.
  19. Position the oil control ring end gaps a minimum of 25 mm (1.0 in) from each other.
  20. Position the compression ring end gaps 180 degrees opposite each other.

  21. Object Number: 1366359  Size: SH
  22. Install the connecting rod bearings (3) to the rod (2) and cap (4).

Full-Floating Piston Pin


    Object Number: 1366372  Size: SH
  1. Install the retaining clip. The clip should be seated in the groove of the pin bore.

  2. Object Number: 35866  Size: SH
  3. Install the piston pin to the piston and connecting rod.
  4. Install the retaining clip. The clip should be seated in the groove of the pin bore.

  5. Object Number: 1336810  Size: SH

    Important: When installing piston rings, use a ring expander plier type tool. Do not roll the rings into the grooves of the piston. Use caution and care to expand the rings only slightly larger than the outside diameter (OD) of the piston.

  6. Identify the compression and oil control rings for proper installation. The upper compression ring can be identified by a paint mark (3) located 180 degrees from the end gap. The lower compression ring can be identified by a paint mark (3) located 90 degrees from the end gap. Both rings should be installed with the orientation marks (1, 2) facing the top of the piston.

  7. Object Number: 490763  Size: SH
  8. Using piston ring pliers, install the piston rings onto the piston.
  9. Position the oil control ring end gaps a minimum of 25 mm (1.0 in) from each other.
  10. Position the compression ring end gaps 180 degrees opposite each other.

  11. Object Number: 1366359  Size: SH
  12. Install the connecting rod bearings (3) to the rod (2) and cap (4).