New piston rings should only be fitted if the cylinder is still within the wear limits in terms of ovality (maximum 0.03 to 0.05 mm). The one-sided movement of the connecting rod causes oval wear to the cylinder. Mounting your new piston rings in a cylinder above the wear limit increases the problem of oil consumption and higher crankcase pressure.
After fitting new piston rings, a running-in period must be taken into account; the new piston rings must be adapted to the operating pattern of the old cylinder. A new cylinder-piston combination may require 10,000 km for maximum sealing, with an old cylinder equipped with new piston rings, this can be 3 times longer.
The most important thing is that you only renew piston rings when the final clearance and the clearance in height are outside the wear limits and the ovality of the cylinder allows it. If the ovality is outside the wear values, fit a new set of pistons and cylinders.
Installation Instructions
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