Crankshaft: Service and Repair

PISTON AND CRANKSHAFT
DISASSEMBLY
1. Place engine on a work stand.
2. Remove timing chains. Service and Repair
3. Remove pistons with connecting rods.








NOTE:
^ To disassemble piston and connecting rod, first remove snap rings. Heat piston to 60 - 70� C (140 - 158� F) then use piston pin press to remove pin.
^ When piston rings are not replaced, make sure that piston rings are mounted in their original positions.
^ When replacing piston rings, if there is no punchmark, install with either side up.





4. Remove main bearing cap and crankshaft.

NOTE: Before removing main bearing cap, measure crankshaft end play. Bolts should be loosened in two or three steps.

ASSEMBLY

Piston





1. Install new snap ring on one side of piston pin hole.





2. Heat piston to 60 - 70° C (140 - 158° F) and assemble piston, piston pin, connecting rod and new snap ring. Align the direction of piston and connecting rod. Numbers stamped on connecting rod and cap correspond to each cylinder. After assembly, make sure the connecting rod swings smoothly.





3. Set piston rings as shown.

NOTE:
^ When piston rings are not replaced, make sure that piston rings are mounted in their original positions.
^ Install new piston rings either side up if there is no punchmark.





^ Align piston rings so that end gaps are positioned as shown.

Crankshaft





1. Set main bearings in their proper positions on cylinder block and main bearing cap.
^ Confirm that correct main bearings are selected by using the plastigage method or the bore gauge/micrometer method.
^ Apply new engine oil to bearing surfaces.
2. Install crankshaft and main bearing caps and tighten bolts to 46 - 56 Nm (34 - 41 ft. lbs.).
^ Apply new engine oil to the bolt thread and seat surfaces.
^ Prior to tightening bearing cap bolts, shift crankshaft back and forth to properly seat the bearing cap.





^ Tighten bearing cap bolts gradually in two or three steps. Start with center bearing and move outward as shown in figure.
^ After securing bearing cap bolts, make sure crankshaft turns smoothly by hand.





3. Measure crankshaft end play. The crankshaft end play standard value 0.05 - 0.18 mm (0.0020 - 0.0071 inch). The limit is 0.3 mm (0.012 inch). If beyond the limit, replace thrust bearing with a new one.
4. Install connecting rod bearings in connecting rods and connecting rod caps.





^ Confirm that the correct bearings are used and install the bearings so that the oil hole in each connecting rod aligns with the oil hole of the bearing. Testing and Inspection
^ Apply new engine oil to bearing surfaces, bolt threads and seating surfaces.





5. Install pistons with connecting rods into corresponding cylinders with tool shown.
^ Make sure connecting rod does not scratch cylinder wall.
^ Make sure connecting rod bolts do not scratch crank shaft pin journals.
^ Arrange so that front mark on piston head faces toward front of engine.
^ Apply new engine oil to piston rings and sliding surface of piston.
6. Install the connecting rod caps.





NOTE: Apply new engine oil to the bolt threads and nut seating surfaces. Tighten connecting rod cap nuts to 14 - 16 Nm (10 - 12 ft. lbs.). Then turn the nuts another 60 to 65° clockwise with an angle wrench, or if an angle wrench is not available, tighten them an additional 38 - 44 Nm (28 - 33 ft. lbs.)





7. Measure connecting rod side clearance. Connecting rod side clearance: The standard clearance is 0.2 - 0.4 mm (0.008 - 0.016 inch). The limit is 0.6 mm (0.024 inch). If beyond the limit, replace connecting rod and/or crankshaft.