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6. CYLINDER HEAD/CYLINDER/PISTON

6-0

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CYLINDER HEAD/CYLINDER/PISTON

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SERVICE INFORMATION........................................................ 6-3

TROUBLESHOOTING.............................................................. 6-3

CYLINDER HEAD.................................................................... 6-4

CYLINDER/PISTON................................................................. 6-8

Summary of content (13 pages)

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6.
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6. CYLINDER HEAD/CYLINDER/PISTON 〈 SH10AA〉 Torque: 1.1_ Torque: 1.5_ 6-1 1.7kg-m 1.
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6. CYLINDER HEAD/CYLINDER/PISTON 〈 SH10BA〉 Torque: 0.8_ 1.2kg-m Torque: 1.1_ 1.7kg-m (cold) Torque: 1.5_ 1.
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6. CYLINDER HEAD/CYLINDER/PISTON SERVICE INFORMATION GENERAL INSTRUCTIONS • The cylinder head, cylinder and piston can be serviced with the engine installed in the frame. • Before disassembly, clean the engine to prevent dust from entering the engine. • Remove all gasket material from the mating surfaces. • Do not use a driver to pry between the cylinder and cylinder head, cylinder and crankcase. • Do not damage the cylinder inside and the piston surface.
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6. CYLINDER HEAD/CYLINDER/PISTON Spark Plug Cap CYLINDER HEAD REMOVAL 〈 SH10AA〉 Remove the rear carrier. Remove the frame body cover. (2-5) Drain the coolant. Disconnect the thermosensor wire from the thermosensor. Disconnect the water hose from the thermostat housing. Exhaust muffler joint lock nut Remove the spark plug cap. Remove the two joint lock nuts on the front of the exhaust muffler and then remove the two exhaust muffler lock bolts. The installation sequence is the reverse of removal.
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. CYLINDER HEAD/CYLINDER/PISTON Spark Plug Cap CYLINDER HEAD REMOVAL 〈 SH10BA〉 Remove the rear carrier. Remove the frame body cover. (2-5) Fan Cover/Engine Hood Remove the spark plug cap. Remove the three bolts attaching the fan cover to remove the fan cover. Remove the two joint lock nuts on the front of the exhaust muffler and then remove the two exhaust muffler lock bolts. Remove the bolt attaching the engine hood to remove the engine hood. The installation sequence is the reverse of removal.
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6. CYLINDER HEAD/CYLINDER/PISTON COMBUSTION CHAMBER DECABONIZING Remove the carbon deposits from the combustion chamber ＊ Combustion Chamber Avoid damaging the combustion chamber wall and cylinder mating surface. Mating Surface CYLINDER HEAD INSPECTION Check the cylinder head for warpage with a straight edge and feeler gauge. Service Limit: SH10BA: 0.10mm replace if over SH10AA: 0.10mm replace if over Cylinder head Gasket CYLINDER HEAD INSTALLATION Install the cylinder head on the cylinder properly.
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6. CYLINDER HEAD/CYLINDER/PISTON Cylinder Head Bolts Installation Install and tighten the cylinder head bolts diagonally in 2 or 3 times. Torque: 1.5_ 1.7kg-m Install the spark plug. Torque: 1.1_ 1.7kg-m Cylinder head Bolts Cylinder Head Engine Hood Installation 〈 SH10BA〉 Install the engine hood. (6-5) Install the spark plug cap.
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6. CYLINDER HEAD/CYLINDER/PISTON CYLINDER/PISTON CYLINDER REMOVAL Remove the met-in box and seat. Remove the frame body cover. Remove the cylinder head._6-4_ Remove the two exhaust muffler joint lock nuts and two exhaust muffler lock bolts. Remove the exhaust muffler. Remove the cylinder. Remove the cylinder gasket. ＊ Do not pry between the cylinder and crankcase or strike the fins.
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6. CYLINDER HEAD/CYLINDER/PISTON CYLINDER/PISTON INSPECTION Check the cylinder and piston for wear or damage. Clean carbon deposits from the exhaust port area. ＊ Be careful not to damage the cylinder inside wall. Measure the cylinder bore at three levels of A, B and C in both X and Y directions. Avoid the port area. Take the maximum figure measured to determine the cylinder bore. Service Limit: SH10BA: 51.05mm replace if over SH10AA: 51.05mm replace if over Inspect the top of the cylinder for warpage.
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6. CYLINDER HEAD/CYLINDER/PISTON ＊ The cylinder has an A mark or no mark on it. When replacing the cylinder with a new one, use a cylinder having the same mark as the old one. Measure the piston O.D. at a point 5mm from the bottom of the piston skirt. Service Limit: SH10BA: 38.90mm replace if below SH10AA: 38.90mm replace if below Measure the piston-to-cylinder clearance. Service Limit: SH10BA: 0.10mm replace if over SH10AA: 0.10mm replace if over Measure the piston pin hole I.D.
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6. CYLINDER HEAD/CYLINDER/PISTON PISTON RING INSPECTION Measure each piston ring end gap. Service Limits: Top/Second SH10BA: 0.40mm replace if over SH10AA: 0.40mm replace if over ＊ Set each piston ring squarely into the cylinder using the piston and measure the end gap. CONNECTING ROD SMALL END INSPECTION Install the piston pin and bearing in the connecting rod small end and check for excessive play. Measure the connecting road small end I.D. Service Limit: SH10BA: 17.03mm replace if over SH10AA: 17.
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6. CYLINDER HEAD/CYLINDER/PISTON Install a new cylinder gasket on the mating surface between the cylinder and crankcase. Cylinder Gasket Ring Pins Make sure that the ring end gaps are aligned with the piston ring pins in the ring grooves. Lubricate the cylinder inside and piston rings with engine oil and install the piston into the cylinder while compressing the piston rings. ＊ Be careful not to damage the piston. Install the cylinder head. Torque: 1.5_ 1.