Husqvarna SMS4, Руководство по ремонту

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F1.27 Part. N. 8000 H4704 (07-2010)
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ENGINE OVERHAUL
pIstON RINGs CHECk
1. measure:
• Piston rings side clearance
Not conforming to specifications Replace the piston and
piston rings together.
piston ring •
Upper piston ring •
Ring side clearance •
0.030-0.065 mm (0.0012-0.0026 in)
Limit •
0.100 mm (0.0039 in)
Lower piston ring •
Ring side clearance •
0.020-0.055 mm (0.0008-0.0022 in)
Limit •
0.100 mm (0.0039 in)
• Before measuring piston rings side clearance, eliminate
carbon deposits from piston rings and their grooves.
2. Install:
• Piston ring (in the cylinder)
• Level the piston ring in the cylinder with the piston crown.
3. measure:
• Piston ring ends gap
Not conforming to specifications Replace piston ring.
• It is not possible to measure the gap between the scraper ring
expander spacer ends. If the scraper ring gap is excessive,
replace all three piston rings.
piston ring •
Upper piston ring •
Piston ring ends gap (when installed) •
0.10-0.25 mm (0.0039-0.0098 in)
Limit •
0.50 mm (0.0197 in)
Lower piston ring •
Piston ring ends gap (when installed) •
0.10-0.25 mm (0.0039-0.0098 in)
Limit •
0.60 mm (0.0236 in)
scraper ring •
Piston ring ends gap (when installed) •
0.20-0.70 mm (0.0079-0.0276 in)
• a. 40 mm (1.57 in)