Connecting Rod: Service and Repair
PISTON & CONNECTING RODREMOVAL
1. Remove the cylinder head.
2. Remove the oil pan.
3. Remove top ridge of cylinder bores with a reliable ridge reamer before removing pistons from cylinder block. Be sure to keep tops of pistons covered during this operation. Mark piston with matching cylinder number (Fig. 74).
CAUTION: DO NOT use a number stamp or a punch to mark connecting rods. Damage to connecting rod could occur.
4. Using a permanent ink or paint marker, identify cylinder number on each connecting rod cap (Fig. 75).
5. Pistons will have a stamping in the approximate location shown in (Fig. 74). These stamps will be either a directional arrow or a weight identification for the assembly. L is for light and H is for heavy. These assemblies should all be the same weight class. Service piston assemblies are marked with a S and can be used with either L or H production assemblies. The weight designation stamps should face toward the timing belt side of the engine.
6. Pistons and connecting rods must be removed from top of cylinder block. Rotate crankshaft so that each connecting rod is centered in cylinder bore.
7. Remove connecting rod bolts and cap. Care should be taken not to damage the fracture rod and cap surfaces.
NOTE: Do not reuse connecting rod bolts.
CAUTION: Care must be taken not to damage the fractured rod and cap joint surfaces, as engine damage many occur.
8. To protect crankshaft journal and fractured rod surfaces, install Special Tool 8189, connecting rod guides onto connecting rod (Fig. 76). Carefully push each piston and rod assembly out of cylinder bore.
9. Remove Special Tool 8189, connecting rod guides and re-install bearing cap on the mating rod.
NOTE: Piston and rods are serviced as an assembly.
10. Repeat procedure for each piston and connecting rod assembly.
11. Remove piston rings.
INSTALLATION
1. Install piston rings on piston.
2. Before installing pistons and connecting rod assemblies into the bore, ensure the compression ring gaps are staggered, and neither is in line with the oil ring rail gap (Fig. 84).
3. Before installing the ring compressor, ensure the oil ring expander ends are butted and the rail gaps are located as shown in (Fig. 84). As viewed from top.
4. Immerse the piston head and rings in clean engine oil, slide the ring compressor, over the piston (Fig. 77). Be sure position of rings does not change during this operation.
5. The weight stamp designation L or H will be in the front half of the piston should face toward the front of the engine (Fig. 74).
6. Rotate crankshaft so that the connecting rod journal is on the center of the cylinder bore. Lubricate connecting rod journal with clean engine oil.
7. Install connecting rod upper bearing half into connecting rod. Install Special Tool 8189, connecting rod guides onto connecting rod (Fig. 76).
8. Insert rod and piston assembly into cylinder bore and carefully guide rod over the crankshaft journal.
9. Tap the piston down in cylinder bore, using a hammer handle. At the same time, guide connecting rod into position on connecting rod journal.
10. Remove Special Tool 8189, connecting rod guides.
NOTE: The connecting rod cap bolts should not be reused.
11. Before installing the NEW bolts, the threads should be coated with clean engine oil.
12. Install connecting rod lower bearing half into connecting rod cap. Install connecting rod cap.
13. Install each bolt finger tight then alternately torque each bolt to assemble the cap properly.
14. Tighten the connecting rod bolts using the 2 step torque-turn method. Tighten according to the following values:
CAUTION: Do not use a torque wrench for the second step.
1. Tighten the bolts to 27 Nm (20 ft. lbs.).
2. Tighten the connecting rod bolts an additional 1/4 TURN.
15. Using a feeler gauge, check connecting rod side clearance (Fig. 78). (Refer to - ENGINE -SPECIFICATIONS) for connecting rod side clearance.
16. Install the cylinder head.
17. Install the oil pan.