Valve Seats - HARTFORD CG-125 Service Manual

Hartford Industrial Co., Ltd.
head,valves and piston
4.4.9 Inspect / overhaul the

valve seats

Remove the carbon deposits from the
inlet and exhaust valves.
Place a smear of red ink on the valve
contact face and rotate the valve in
it' s seat twice.Observe the width and
regularity of the contact patch
Replace with new parts valves
that are bent or burnt
If the valve seat is pitted or burnt it
must be ground
Use 4 to 5 kg of pressure and a right
– left rocking motion to re-finish the
valve seat surface. Use oil.First use
a 45 degree cutter to face the valve
seat, then a 32 degree cutter to face
the next ¼ of the total seat width. The
60 degree cutter is used to face the
next ¼ of the total seat width. Finally,
the 45 degree cutter is used again to
finish the lower part of the seat If
the valve seat edge is too high, use
a 37.5 degree angle cutter to remove
material, and a 45 degree cutter to
correct the angle If the valve seat
edge is too low, use a 63.5¢Xdegree
angle cutter to remove material,and
a 45 degree cutter to correct the angle.
Remove the abrasive
residue from grinding to prevent
premature wear and encourage god
sealing of the valve.
4.Cylinder,cylinder
NO CG
4-9
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