Valve Seat Refacing; Valve Lapping - Cub Cadet 7360SS Service Manual

(b)The valve margin must be not less than
the limit. If the margin seems to be less
than the limit when the valve is refaced,
replace the valve.

(6)Valve seat refacing

(a)Before refacing the valve seat, check the
clearance between the valve and guide,
and replace the guide if necessary.
(b)Cut the valve seat with a valve seat
cutter(commercially available), or grind
it with a valve seat grinder, and finish
the width of valve seat and the angle of
seat face to the correct values.
Item Standard
Angle of
seat face
Width of 1.3 to 1.8
valve seat (0.051 to 0.071)
(c)After refacing the valve seat, put lapping
compound on the valve face and lap the
valve in the valve seat.
Unit:mm(in.)
Limit
45
2.5
(0.098)

(7)Valve lapping

Be sure to lap the valves in the seas after
refacing or replacing the valves or valve
seats.
(a)Put a small amount of lapping compound
on the valve face.
a)Do not put lapping compound on the
valve stem.
b)Use a lapping compound of 120 to 150
mesh for initial lapping and a compound
of finer than 200 mesh for finish lapping.
c)Mixing the compound with a small
amount of engine oil will help put the
compound on the valve face uniformly.
(b)Using a lapping tool, hold the valve
against the seat and rotate it only a part
of a turn, then raise the valve off its seal,
rotating it to a new position. Press the
valve against the seal for another part of
a turn. Repeat this operation until the
compound wears and loses its cutting
property.
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