GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • EN 46121 Connecting Rod Guide Pin Set
    • EN-46745 Piston Pin Clip Remover/Installer

Piston and Piston Pin Installation Procedure


    Object Number: 1960678  Size: SH

    Important: 

       • The arrow located on top of the piston must point toward the front of the cylinder block.
       • The connecting rod is non-directional and may be assembled/reassembled to the piston in either direction.

  1. Lubricate the piston pin (2) bores in the piston (1) and the connecting rod (3) with clean engine oil.
  2. Assemble the piston (1) and piston pin (2) to the connecting rod (3). Correctly orient the piston (1) when reusing a marked connecting rod (3).
  3. Align the piston pin (2) bore with the connecting rod (1) pin bore.
  4. Slide the piston pin (2) into the piston (1) and the connecting rod (3).

  5. Object Number: 1959119  Size: SH

    Important: New piston pin retainers must be used. Never reuse the piston pin retainers.

  6. Install NEW piston pin retainers using the EN-46745 . Align the EN-46745 to the notch (1) in the piston.
  7. Ensure that the piston pin retainers are fully seated in their grooves.
  8. Repeat these procedures for the remaining pistons.

Piston Ring Installation Procedure


    Object Number: 1960679  Size: SH
  1. Correctly orient the oil control ring expander (1) as shown before installation. The ends of the oil control ring expander (1) must be facing toward the top of the piston.

  2. Object Number: 1960680  Size: SH
  3. Using a piston ring expander, install the oil control ring assembly using the following procedure:
  4. 2.1. Install the expander ring (1).

            Important: Make sure that you DO NOT overexpand the piston ring. Overexpanding the piston rings will distort or crack the rings.

    2.2. Install the 2 oil scraper rings (2). Expand the rings only enough to clear the piston diameter.

    Object Number: 1959116  Size: SH

    Important: Make sure that you DO NOT overexpand the piston ring. Overexpanding the piston rings will distort or crack the rings.

    Important: Install the second piston ring (1) onto the piston (3) using the ring expander (2).

  5. Install the second piston ring (1) onto the piston (3).

  6. Object Number: 1959116  Size: SH

    Important: Make sure that you DO NOT overexpand the piston ring. Overexpanding the piston rings will distort or crack the rings.

    Important: Install the top piston ring (1) onto the piston (3) using the ring expander (2).

  7. Install the top piston ring (1) onto the piston (3).

  8. Object Number: 1960682  Size: SH
  9. Once the rings are installed, set the ring gaps for the oil control, second and top ring as follows. Use the piston location arrow for reference.
  10. 5.1. Lower oil control ring - position (1).
    5.2. Upper oil control ring - position (2).
    5.3. Top Ring - position (3).
    5.4. Oil control ring expander - position (4).
    5.5. Second ring - position (5).

Connecting Rod Bearing Installation Procedure


    Object Number: 1960683  Size: SH

    Important: If the connecting rod bearings (1) have been used in a running engine, you must replace them with NEW connecting rod bearings (1) for reassembly.

  1. Clean the connecting rod (2) and the connecting rod cap bearing bore with a lint-free cloth.
  2. Clean all the oil from behind the connecting rod bearing (1) halves.
  3. Install new upper connecting rod bearings (1) into position. Roll the connecting rod bearings (1) into position so that the lock tang engages the alignment slot. The connecting rod bearings (1) must fit flush in the connecting rod (2).

  4. Object Number: 1960684  Size: SH
  5. Install the EN 46121  (1) into the connecting rod bolt holes.

  6. Object Number: 1960686  Size: SH
  7. Install new lower connecting rod bearings (1) into position in the connecting rod cap (2). Roll the connecting rod bearings (1) into position so that the lock tang engages the alignment slot. The bearings must fit flush with the connecting rod cap (2).