GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 24086-C Piston Pin Remover/Installer Set


    Object Number: 688111  Size: SH

    Important: This procedure is to be used for oversized pistons only. Standard size pistons are supplied as an assembly consisting of a piston, piston pin, connecting rod and piston rings. Assemble the piston for the specific cylinder with the connecting rod for the corresponding crankshaft journal.

  1. Install fork insert J 24086-310 into fixture J 24086-10, which are part of J 24086-C .

  2. Object Number: 688105  Size: SH
  3. Lubricate the piston pin with clean engine oil.
  4. Important: Ensure that the marks on the piston and connecting rod are aligned the same as when removed. If installing a new piston, ensure that the arrow on top faces towards the front of the engine. If no identification marks were made during disassembly, ensure that the flat area on the bottom of the piston pin skirt is aligned with the small dimple above the connecting rod crankshaft bearing bore.

  5. Assemble the piston, connecting rod and adapter J 24086-6A and install onto fixture J 24086-10, which are part of J 24086-C .

  6. Object Number: 533486  Size: SH
  7. Adjust installation pin J 24086-9 to G-4.

  8. Object Number: 533483  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.

  9. Insert pin J 24086-9 through fixture J 24086-10, which are part of J 24086-C and to the piston pin.
  10. Press pin J 24086-9 until it bottoms on fixture J 24086-10.

  11. Object Number: 909632  Size: SH

    Notice: Use a piston ring expander to install the piston rings. The rings may be damaged if expanded more than necessary.

    Important: To provide an effective compression seal, the ring gaps must be staggered a minimum of 90 degrees.

  12. Using piston ring pliers, install the piston rings onto the piston.
  13. 7.1. Install the oil control ring spacer into the bottom groove of the piston.
    7.2. Install the lower oil control ring. The oil control rings do not have a dimple or orientation mark and may be installed in either direction.
    7.3. Install the upper oil control ring.
    7.4. Install the middle compression ring with the dot facing up.
    7.5. Install the top compression ring in either direction. The ring has no orientation markings.