Piston & Rod Assembly
- Ensure connecting rod and connecting rod cap are marked with corresponding cylinder number for installation reference before removing. Shape of piston varies from driver's side of engine to passenger's side of engine. Pistons for driver's side of engine are marked with LH and 2L and pistons for passenger's side of engine are marked with RH and 2R. (Scheme 35)
- Piston must be installed with front mark on top of piston toward front of engine. (Scheme 35) Connecting rod cap must be installed so outside mark (protrusion) is facing proper direction depending on which side of engine piston is installed. (Scheme 35)
- Check for movement of piston back and forth on piston pin. Replace piston and piston pin assembly if movement exists. When removing piston from connecting rod, remove snap rings from piston. Note direction of piston installation on connecting rod in relation to front mark on piston and outside mark on connecting rod. (Scheme 35)
- Heat piston to 140°F (60°C) in water. Using hammer and brass drift, tap piston pin from piston and connecting rod. Separate piston from connecting rod.
- Using caliper, measure outside diameter of connecting rod bolt at center of bolt, just above threads. Replace connecting rod bolt if outside diameter is less than.2756" (7.000 mm).
- Measure piston diameter at 1.211" (30.75 mm) from top of piston at 90-degree angle to piston pin. Different diameter pistons are used. Piston diameter is determined by size mark ("1", "2" or "3") stamped on top of piston. (Scheme 36) Ensure piston and piston pin diameter are within specification. See «PISTONS, PINS & RINGS»(ref-3005-S39627407302000041700000) table under ENGINE SPECIFICATIONS.
- Ensure connecting rod pin bushing bore diameter, crankpin bore diameter, bend and twist are within specification. See «CONNECTING RODS»(ref-3005-S20739515232000041700000) table under ENGINE SPECIFICATIONS. NOTE: Crankpin bore diameter is identified by size mark ("1", "2", "3" or "4") stamped on connecting rod cap. see scheme 42
- Bushing in connecting rod may be replaced if bore diameter is not within specification. Ensure bushing oil hole aligns with connecting rod oil hole. Hone bushing to obtain correct piston pin-to-rod clearance. See «PISTONS, PINS & RINGS»(ref-3005-S39627407302000041700000) table under ENGINE SPECIFICATIONS. NOTE: Piston pin should slide into piston using thumb pressure with piston heated to 140°F (60°C).
- To reassemble, install NEW snap ring in one side of piston. Heat piston to 140°F (60°C) in water. Install piston on connecting rod with front mark on top of piston aligned with outside mark on connecting rod. (Scheme 35) Coat piston pin with engine oil and install. Install NEW snap ring on other side of piston.
