Pistons
The piston assembly must be dismantled for inspection of mating surfaces between piston skirt and piston crown and for inspection and cleaning of cooling oil spaces.
Piston crown
Visual inspection: The combustion space must be checked for corrosion and/or burning
marks. If marks deeper than 2 mm are found the piston crown should be replaced. Deposits in the cooling oil space thicker than 0.5 mm is an indication of contaminated lubricating oil. Such extensive deposit layers can cause overheating of the piston crown.
Crack detection test: A crack detection test by use of liquid penetrant or, preferably, magnetic particle detection method should be performed, comprising all surfaces. No cracks are allowed.