Piston and Connecting Rod Assemble L98, LS2

Tools Required

EN 46121 Connecting Rod Guide Pin Set

1. Assemble the piston and connecting rod with the notch (1) on the piston and the painted mark (2) on the connecting rod facing the front of the engine.

When installing the piston and connecting rod assembly, the mark on the top of the piston (1) and the painted mark (2) on the connecting rod should face the front of the engine.





Important: Make sure the retainer (1) is seated in the groove.

2. Install the retainer (1).



3. Install the piston pin (2) to the piston (3) and connecting rod (4).

Important: Make sure the retainer (1) is seated in the groove.

4. Install the retainer (1).

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. Using a piston ring expander, install the oil control ring assembly using the following procedure:

2.1.	Install the expander ring (2).

Important: Make sure that you do not over expand the piston ring. Over expanding the piston rings will distort or crack the rings.

2.2.	Install the 2 oil scraper rings (1). Expand the rings only enough to clear the piston diameter.





Important: Make sure that you do not over expand the piston ring. Over expanding the piston rings will distort or crack the rings.

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

3. Install the second piston ring (2) onto the piston (3).




Important: Make sure that you do not over expand the piston ring. Over expanding the piston rings will distort or crack the rings.

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

4. Install the top piston ring (2) onto the piston (3).



5. 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.

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).

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. Install the EN 46121  (1) into the connecting rod bolt holes.



5. 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).

Piston and Connecting Rod Assemble LS3

1. Install the retainer. The retainer should be seated in the groove of the pin bore.



2. Assemble the piston and connecting rod. The mark (1) on the top of the piston and the tab (2) on the side of the connecting rod should be facing the same direction.



3. Install the piston pin to the piston and connecting rod.
4. Install the retainers. The retainers should be seated in the groove of the pin bore.




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.

5. Using piston ring pliers, install the piston rings onto the piston. The dimple or mark on the piston ring should face 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.
6. Position the oil control ring end gaps a minimum of 25 mm (1.0 in) from each other.
7. Position the compression ring end gaps 180 degrees opposite each other.



8. Install the connecting rod bearings to the rod and cap.