|
|
EM-232 < DISASSEMBLY AND ASSEMBLY > [VK56DE] ENGINE UNIT • Measure point ″ H ″ . Piston to Cylinder Bore Clearance • Calculate by using diameter of the piston skirt and the cylinder bore diameter (direction X, position B). (Clearance) = (Cylinder bore diameter) – (piston skirt diameter) • If calculation exceeds the limit, replace piston/piston pin assembly. Reboring Cylinder Bore 1. Cylinder bore size is determined by adding piston-to-bore clearance to piston diameter (A). 2. Install main bearing caps, and tighten them to the specified torque. Otherwise, cylinder bores may be dis- torted in final assembly. 3. Cut the cylinder bores. NOTE: • When any cylinder needs boring, all other cylinders must also be bored. • Do not cut too much out of cylinder bore at one time. Cut only 0.05 mm (0.0020 in) or so in diameter at a time. 4. Hone cylinders to obtain the specified piston-to-bore clearance. NOTE: Measurement should be done after cylinder bore cools down. CRANKSHAFT MAIN JOURNAL DIAMETER • Measure diameter of crankshaft journals. • If measurement is out of standard, measure the main bearing oil clearance. Then use the undersize bearing. CRANKSHAFT PIN JOURNAL DIAMETER Distance from the top : 39 mm (1.54 in) KBIA2545E Standard : 0.010 - 0.030 mm (0.0004 - 0.0012 in) Limit : 0.08 mm (0.0031 in) Rebored size calculation: D = A +B - C Standard : 63.940 - 63.964 mm (2.5173 - 2.5183 in) 2010 Pathfinder |