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disegno 1
• piston:
- There must not be any signs of seizure or deep cracks.
- Check the wear by measuring the piston at 21,7mm from the bottom keeping the
measuring instrument at a right angles to the axis pin.
Height limits:
SELECTION A: 69.89mm
SELECTION B: 69.90mm
SELECTION C: 69.91mm
• The pin must not be blue because that indicates a high working temperature and the
external diameter must not be less than 17.990mm.
• Measure the slack between the piston ring and its seat: slack height limit 0.1mm.
• Piston ring: insert a piston ring in the cylinder one by one, by using the piston, so it is
a square, measure the gap that is created between the two ends of piston ring using
feeler gauge. Height limit: 0.7mm
• Crankshaft: supporting the crankshaft at the two working points of oil seals, with two
comparators, measure the centering at the two working points of the bearings, marked
on diagram 2 with the letter A. Height limit: 0.05mm