Piston and Connecting Rod Assemble

Special Tools

• EN-46745  Piston Pin Clip Remover/Installer
• EN-46745-4  Piston Pin Clip Remover/Installer Adapter

For equivalent regional tools, refer to Special Tools .

1. Courtesy of GENERAL MOTORS COMPANY

   NOTE:

   Install the piston onto the connecting rod with the arrow on top of the piston oriented to the same side as the cast feature at the split line of the connecting rod.

   The arrow (1), on the top of the piston, must go to the front of the block.

2. The feature at the split line (4), located on one side of the connecting rod, must go to the front of the block.
3. Assemble the connecting rod (3) and the piston (2).

4. Courtesy of GENERAL MOTORS COMPANY

   CAUTION:

   Install the piston pin retainers correctly in the retaining groove during assembly in order to avoid engine damage.

   NOTE:

   Use NEW retainers. Two retainers hold each piston pin in place.

   NOTE:

   Use the appropriate adapter for EN-46745  installer to install the retainers. The appropriate adapter will fit the piston pin ID and allow the ring to be removed or installed.

   • For LCV/LKW/LD4 piston pin, use EN-46745-2  adapter.
   • For LTG piston pin, use EN-46745-4  adapter.

   Use the following procedure to assemble the piston pin and the retainer:

   1. Coat the piston pin with oil.
   2. Install one NEW piston pin retainer into the retaining groove using EN-46745  installer and the appropriate adapter. Rotate the retainer until it is fully seated in the groove.
   3. Install the connecting rod and the piston pin.

      Push the piston pin until it bottoms in the previously installed retainer.

   4. Install the second NEW piston pin retainer, using EN-46745  installer (1) and the appropriate adapter.
   5. Ensure that the piston moves freely.

5. Courtesy of GENERAL MOTORS COMPANY

   The piston ring end gaps must be positioned 90 degrees to each other.

   • Upper compression ring joint (1)
   • Lower compression ring joint (2)
   • Upper oil ring rail joint (5)
   • Oil ring rail spacer joint (4)
   • Lower oil ring rail joint (3)

6. Courtesy of GENERAL MOTORS COMPANY

   CAUTION:

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

   Install the following components of the oil control ring assembly:

   1. The piston oil ring rail (5)
   2. The piston oil ring rail spacer (4)
   3. The second piston oil ring rail (3)
7. Install the piston lower compression ring (2). Place the manufacturer's mark facing up.
8. Install the piston upper compression ring (1).