ZHEJIANG KAYO MOTOR CO., LTD.
4
．
Remove the left cover of the cylinder head.
5
．
Remove the 3 GB/T 5783/M5×12 hexagon head bolts that fasten the timing driven sprocket and
remove the timing driven sprocket from the camshaft.
6
．
Remove one M6×20 bolt connecting the cylinder head and the cylinder body.
7
．
Remove the cylinder head.
8
．
Remove the positioning pins on the A and B bolts, the flange bushing and the rectangular ring
11.5×16×2.5, and remove the cylinder head gasket.
Disassemble the cylinder head
The disassemble steps of the cylinder head are as follows:
1. Remove the valve cover.
2. Remove 2 bolts GB/T 5787/M6×20 which use to fasten the right cover of the cylinder head
3. Remove the right cover and the gasket of the cylinder head .
4. Take out the inlet and exhaust rocker arm shafts, inlet and exhaust rocker arms, limit plates and camshaft
components.
5. Depress the valve spring with a valve remover and remove the valve lock clip.
6. Loosen the valve remover and remove the valve spring seat, valve spring and valve.
Note
：
1. In order to prevent permanent deformation of the valve spring, only the valve lock clip can be removed, and the
valve spring cannot be compressed excessively.
2. All removed parts should be marked to ensure that they reach the original assembly position during assembly.
3. When disassembling the gasket, ensure that the gasket is in good condition. If it is damaged, replace it with a
new gasket during assembly to avoid engine oil leakage.
。
Inspection of valves and valve
springs
The inspection steps for valves and valve springs are as follows:
1. Check whether the valve is bent or the valve stem is abnormally worn, and measure the outer diameter of the
valve stem.
Repair limit value:
Intake
：
φ4.96mm
Exhaust
：
φ4.94mm
2. Maintenance limit value of the width of the contact surface
：
1.5mm
3. Check the valve spring for abnormal wear and measure the free length of the spring:
Standard value
：
Outer valve spring 35.55mm
Inner valve spring 32.78 mm
Repair limit value
：
Outer valve spring 34.80mm
Inner valve spring 32.03mm
Note: If the contact surface of the valve is rough, abraded unevenly or the contact with the valve seat is
abnormal, the sealing performance cannot be guaranteed, and the valve should be replaced.
。
Inspection of rocker arm and
rocker shaft
The inspection steps of the rocker arm and rocker shaft are as follows:
1. It is necessary to check whether the arc surface of the rocker arm is damaged, whether the valve adjusting
screw and nut rotate flexibly. If the phenomenon of wear or damage is serious, a new rocker arm needs to be
replaced.
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