Piston & Rod Assembly
WARNING: This page is about a different variant/trim than selected.
CAUTION:
Connecting rod bolts are torque-to-yield design. DO NOT reuse bolts if loosened or removed.
- Before installing piston/connecting rod assemblies in bore, check pistons for taper and elliptical shape. Check for misaligned, bent or twisted connecting rods. Check connecting rod crankshaft journal for excessive wear, taper and scoring.
- Ensure piston ring end gaps are in proper position. See Figure. No. 1 and 2 rings have different cross section. Ensure No. 2 ring is installed with dot facing up. Replace any piston/connecting rod assemblies not meeting specification. See PISTONS, PINS & RINGS table under ENGINE SPECIFICATIONS.
- Pistons are marked with "F" on piston pin bore surface. All "F" marks must be facing forward when piston and connecting rod assemblies are installed.NOTE: Coating material is applied to pistons after machining process. Measuring outside diameter of coated piston will not provide accurate results.CAUTION: DO NOT remove piston pin from coated piston/connecting rod assembly.
- DO NOT substitute old style pistons for new coated pistons. Coated pistons are preassembled with piston, piston pin and connecting rod, and must be replaced in complete sets. Coated piston/connecting rod assemblies can be used to replace old style pistons as a complete set.
- To correctly select proper size piston, a bore gauge capable of reading .0001" (.003 mm) increments must be used. If bore gauge is not available, DO NOT use inside micrometer.
- Measure cylinder bore 1.95" (49.5 mm) below top of bore, and in line with axis of crankshaft ("B"). Take a second reading at 90 degrees to first reading ("A"). See Fig 1.NOTE: Installing coated piston into cylinder bore requires slightly more pressure than non-coated piston.