7. Check for damage or cracks in the cylinders.
8. Check the top surface of the cylinder block for flatness. If the top surface exceeds the limit, grind to the
minimum limit or replace.
Standard value
Flatness of gasket surface : Max. 0.03mm (0.0012in.)
Service limit
Flatness of gasket surface : 0.05mm (0.0020in.)
When the cylinder head is assembled, grinding less than 0.2mm (0.008in.) is permissible.
Boring Cylinder
1. Oversize pistons should be selected according to the largest bore cylinder.
Identification Mark
Size
0.25
0.50
0.25mm (0.010in.)
0.50mm (0.020in.)
The size of piston is stamped on top of the piston.
2. Measure the outside diameter of the piston to be used.
3. According to the measured O.D., calculate the new bore size.
New bore size = Piston O.D + 0.01 to 0.03 mm (0.0004 to 0.0012 in.) (clearance between piston and cylinder)
- 0.01 mm (0.0004 in.) (honing margin.)
4. Bore each of the cylinders to the calculated size.
To prevent distortion that may result from temperature rise during honing, bore the cylinder holes in the
firing order.
Page 2 of 3
24.04.2008
http://www.hmaservice.com/viewer/content.asp?IsPrint=true&imgnum=1&print_title...
