Qianjiang QJ150T-10, Operation And Maintenance Manual, Page: 93 / 131

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Measure the outer diameter of the valve bar.
Allowable limit ： 4.95mm 。
Examine the valve guide. Use reamer to clean out the
carbon deposit in the valve guide before examination.
Note: the reamer should undergo clockwise rotation while
anticlockwise rotation should be inhibited.
Measure the inner diameter of each valve guide.
Allowable limit ： Take in/discharge ： 5.03mm 。
he clearance between the valve and the valve guide.
Allowable limit
：
induction valve: 0.08mm 。
exhaust valve: 0.10mm
。
11.7 Replace the valve guide
Note: if the clearance between the valve and the valve
guide exceeds the allowable limit, valve guide should be
replaced. After the replacement of valve guide, the surface
of the portal frame ring of the valve should be conditioned.
Put the valve guide into the refrigerating chamber of the
refrigerator for an-hour cooling.
Use electric furnace or thermal bake oven to heat the
cylinder head to 100-150
℃ .
Fix the cylinder head. Take advantage of valve guide
dismounting tools to dismantle the valve guide form the
upper side of the cylinder.
Opener for valve
guiding pipe
Tester
Valve reamer