Yingang YG48Q-5A, Руководство по обслуживанию

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YG48Q-5A Maintenance ManualCylinder Head, Cylinder and Piston
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Cylinder head, cylinder and piston
Maintenance notice Cylinder head
Troubleshooting Cylinder
Cylinder head cover Piston
Camshaft
Maintenance notice
The lubrication of the camshaft and rocker arm is implemented by pumping oil by the oil pump through the oil troughs of
the cylinder, cylinder head and cylinder head cover; before assembling, please check whether the oil troughs are
unobstructed and clean them up properly.
Before assembling, clean all parts and components with cleaning agent and dry them with compressed air.
While assembling, coat engine oil and molybdenum disulfide lubricant on the protruding surface of the camshaft for
preliminary lubrication.
Be careful not to damage the cylinder wall and piston.
Technical specifications & maintenance benchmark
Item Standard value Maintenance limit value
Camshaft
Camshaft lift:IN
5.62mm 5.56mm
Camshaft lift:EX 5.38mm 5.32mm
Cylinder head Planeness 0.03mm 0.05mm
Valve spring
Internal spring free
length
36.5mm 36mm
External spring free
length
36.5mm 36mm
Valve
IN Valve stem
external diameter
φ
5mm
φ
4.975mm
Conduit inner
diameter
φ
5mm
φ
5.012mm
EX Valve stem
external diameter
φ
5mm
φ
4.955mm
Conduit inner
diameter:
φ
5mm
φ
5.012mm
Valve clearance
IN 0.05mm
～
0.06mm /
EX
0.05mm
～
0.06mm
/
Cylinder
Internal diameter
φ
39.00mm
～φ
39.015mm
φ
39.015mm
Roundness / 0.003
Cylindricity / 0.004