User manual SYM AW12W-A

[. . . ] In addition, please refer to the manual contents in detail for the model you serviced in inspection and adjustment. The first chapter covers the general information and the trouble diagnosis. The second chapter covers the periodic maintenance information and the special tool models. The third to the 11th chapters cover the engine and the driving systems. [. . . ] Clean residues and foreign materials on cylinder head matching surface. Caution Do not damage the matching surface of cylinder head. 6-7 To this chapter contents 6. Cylinder Head / Valve Cylinder Head Inspection Check if spark plug and valve holes are cracked. Measure cylinder head warp with a straightedge and thickness gauge. Service limit: 0. 05 mm Camshaft Inspect cam lobe height for damaged. Service Limit: IN: Replacement when less than 34. 860mm EX: Replacement when less than 34. 725mm Inspect the camshaft bearing for looseness or wear out. If any damage, replace whole set of camshaft and bearing. Rocker Arm Measure the cam rocker arm I. D. , and wear or damage, oil hole clogged?Service Limit: Replace when it is less than 12. 080 mm. Rocker Arm Shaft Measure the active O. D. of the cam rocker arm shaft and cam rocker arm. Service Limit: Replace when it is less than 11. 936 mm. Calculate the clearance between the rocker arm shaft and the rocker arm. Service Limit: Replace when it is less than 0. 10 mm. 6-8 To this chapter contents 6. Cylinder Head / Valve Valve spring free length Measure the free length of intake and exhaust valve springs. Grind valve seat with a rubber hose or other manual grinding tool. Caution Do not let emery enter into between valve stem and valve guide. Clean up the emery after corrected, and apply with engine oil onto contact faces of valve and valve seat. Remove the valve and check its contact face. Caution Replace the valve with new one if valve seal is roughness, wear out, or incomplete contacted with valve seat. Valve seat width Valve seat inspection If the valve seat is too width, narrow or rough, corrects it. Valve seat width Service limit: 1. 6mm Check the contact condition of valve seat. Valve seat grinding The worn valve seat has to be ground with valve seat chamfer cutter. Refer to operation manual of the valve seat chamfer cutter. Use 45° valve seat chamfer cutter to cut any rough or uneven surface from valve seat. Roughness Caution After valve guide had been replaced, it has to be ground with 45° valve seal chamfer cutter to correct its seat face. Use 32° cutter to cut a quarter upper parts out. 45° Old valve seat width 32° 6-11 To this chapter contents 6. Cylinder Head / Valve Use 60° cutter to cut a quarter lower parts out. Remove the cutter and check new valve seat. Old valve seat width 60° Use 45° cutter to grind the valve seat to specified width. Caution Make sure that all roughness and uneven faces had been ground. Grind valve seat again if necessary. 1. 0mm 45° Coat the valve seat surface with red paint. Install the valve through valve guide until the valve contacting with valve seat, slightly press down the valve but do not rotate it so that a seal track will be created on contact surface. Contact surface too high Old valve seat width Caution The contact surfaces of valve and valve seat are very important to the valve sealing capacity. 32° If the contact surface is too high, grind the valve seat with 32° cutter. Then, grind the valve seat to specified width. [. . . ] Visual check: 1) Check the outside of canister for damage. Leakage test: 1) Disconnect the Purge Control Valve hose, and connect a T-type hose connector to a pressure gauge and a pressure source as shown below: Fuel tank Pressure gauge Pressure source Activated-carbon canister Plugged 2) Plug canister vent. 3) Apply 100mmAq into pressure source inlet then plug it. The pressure at the gauge should not drop to below 10mmAq within 10 seconds. 3. [. . . ]