Rato R80, Руководство по обслуживанию, Страница: 67 / 79

Part IV Disassembly and Maintenance
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pull it out smoothly, the thickness of the gauge at this time is the clearance between the
cylinder and the piston.
Standard Service limit
See Tab. 1-3 See Tab. 1-3
d) Clearance of piston ring side
During inspection, place each ring in its respective piston ring groove. Piston rings shall
rotate freely, to be neither loose nor sluggish. Then measure by inserting a thickness gauge
into the clearance between upper and lower planes of the ring and slot.
Standard Service limit
See Tab. 1-3 See Tab. 1-3
e) Piston ring closing clearance
Put piston ring horizontally into the cylinder, push the ring to working position with piston
head, and then measure its opening clearance by thickness gauge. This clearance shall be
neither too great, nor too small. Too great clearance may make cylinder sealing performance
get bad, while, too small clearance will cause the piston ring to be stuck in the cylinder due
to thermal expansion during operation, causing piston ring breaking or even "cylinder
scraping". Ring opening clearance is small, the opening can be filed by thin flat file. It shall
be placed into the cylinder for inspection while filing, until the clearance is proper.