(4) When the sleeves are worn beyond the service limit, or when any cylinder bore is found to be defective, the sleeve should be replaced with a new one. When the inside surfaces of one of more cylinder bores in the crankcase are found to be defective, it is necessary to refinish the bores by boring. In this case, too, the liners should be replaced with new ones. To replace, proceed as follows: (a) Removal e Fix a boring machine to the crankcase in alignment with the cylinder bore from which a sleeve is to be removed. Aligning should be made at the bottom part of the liner where less abnormal wear has occurred. Bore the sleeve until it reaches 0.5 mm (0.0197 in.) in stock thickness.
Pressing sleeve • When it is necessary to rebore the cylinder bores, press the sleeves into position as in b above, and proceed as follows: • Break the sleeve, exercising care not to damage the inside surface of the cylinder bore. (b) Installation Prepare 0.5 mm (0.0197 in.) oversize cylinder sleeves. It Visually check the inside surfaces of the cylinder bores for condition. It is necessary to rebore the bores if they are damaged. e When it is unnecessary to reb ore the cylinder bores, proceed as in steps below. • Measure. the diameter of cylinder bore and the outside diameter of sleeve.
Select oversize sleeve so that the clearance between the sleeve and the bore is 0.08 mm (0.0031 in.) to 0.145 mm (0.0057 in.). Rebore the cylinder bores so that the clearance between the sleeve and the bore is 0.08 mm (0.0031 in.) to 0.145 mm (0.0057 in.). After pressing the sleeves, rebore and hone them to th t 84 +0.035 (3307 +0.0014. ) em a 0 mm. 0 m .. Specifications Unit· mm (in ) Heat the crankcase to about 300°C (572°F). Press the sleeve into the bores in the crankcase by using a hydraulic press in such a manner to make the top of sleeve protrude by 0.3 to 0.5 mm (0.012 to 0.020 in.) from the crankcase. Then, finish them to be flush with the crankcase.
After pressing the sleeves, rebore and hone them to When replacing the sleeves, use the sleeves of the following part numbers. th t 84 +0.035 (3307 +0.0014. ) em a 0 mm. 0 tn .. Specifications Unit: mm (in.) -21- Cylinder sleeve Sleeve boring dimension Standard 87 -0.010 (3 425 -0.0004) -0.045 . -0.0018 0.5 -oversize 875-0 .010 (3 445 -0.0004) . -0.045 . -0.0018 Part No. 0.0. 1.0. Remarks 30607-50301 87+0.10 +0.07 (3 425 +0.0004) . +0.0028 0 83.5 -0.2 0 (3.287 . ) _0008 Standard 30607-50401 875+0 .10 . +0.07 (3445 +0.0004) . +0.0028 0 83.5 -0.2 0 (3.287 -0.008) Oversize