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　　Hidier Power Group (Beijing) Co. Ltd.Cummins technology expert introduce the Cummins diesel generator valvecomponent repair and inspection:

　　How to repair the Cummins B series vehiclediesel engine valve assembly? Cummins diesel generator valve is compoessed ofthe inlet valve, exhaust valve, valve springs, valve spring seat, valve lockblock, valve stem seal, valve guide (use for repair, original valve guide andcylinder head as a whole), valve seat (use for repair, original valve seat andcylinder head as a whole) and so on. Please see figure 4-1. The valve assemblymust ensure that the valve work reliable, durable, sealed.

　　1. Check the inlet and exhaust valve:

　　(1) Check valve stem diameter

　　If the valve stem diameter measured value isless than the limit value, should be replaced with a new valve.

　　(2) Check the valve sealing strip width

　　Check the valve sealing strip width, pleasesee the figure 4-3. Intake valve seal width is 1.51 mm - 1.81 mm, the exhaustvalve width is 1.86 nun~2.22 --wear limit value is 3

　　When the valve sealing strip width isgreater than the specific value, should use reamer repair hinge valve seatgrinding paste, and then grind the valve, and check the tightness of the valveand valve seat. After grinding, inlet valve and exhaust valve sealing stripwidth is 15 mm-2.Omm.

　　In the detection of valve sealing stripwidth at the same time, should also check the valve subsidence value, when thevalue sinkage exceed the allowable limit of 2.5 mm, required replacement of thevalve and valve seat.

　　(3) check the valve stem straightness

　　Gas latch rod straightness inspection asshown in figure 4-4. Regulation valve stem straightness was ≤ 0.012mm, repair limit value is 0.015 mm. When the valve stemstraightness exceeds the limit value for repair, should alignment orreplacement valve. The valve rod abnormal strain, burns, cracks and rod end hasserious defects such as pits, grooves, and should be replaced with a new valve.