Daewoo GC25E-3 Service Manual

G424 Service Manual Base Engine Service Procedure142
DEN0212
1EN0105
1EN0274
1EN0275
5. Valve Seats
(1) Assemble the valve, than measure the valve stem
projection between the end of the valve stem and the
spring seating surface. If the measurement exceeds the
specified limit, replace the valve seat.
Standard value: 42.05 mm (1.6555 in.)
Limit: 42.55 mm (1.6752 in.)
Valve Seat Reconditioning Procedure
(1) Before correcting the valve seat, check for clearance
between the valve guide and valve and, if necessary,
replace the valve guide.
(2) Correct to obtain the specified seat width and angle.
(3) After correction, valve and valve seat should be lapped
with a lapping compound.
Valve Seat Replacement Procedure
(1) Cut the valve seat to be replaced from the inside to thin
the wall thickness. Then, remove the valve seat.
(2) Rebore the valve seat hole in the cylinder head to a
selected oversize valve seat diameter.
(3) Before fitting the valve seat, cool the valve seat in liquid
nitrogen, to prevent the cylinder head bore from galling.
(4) Using a valve seat cutter, correct the valve seat to the
specified width and angle.
See “Valve Seat Reconditioning Procedure”.
Valve stem end
Valve Projection
Spring seating
surface
Unit : mm(in)
Unit : mm(in)
60˚
60˚
25˚
25˚
43.5˚ to
44˚
0.5 to 1.0
(0.020 to 0.030)
0.5 to 1.0
(0.020 to 0.039)
Cut away
Over size I.D
Height of
valve seat
43.5˚ to 44˚
0.9 to 1.3
(0.035 to 0.051)
0.9 to 1.3
(0.035 to 0.051)

Daewoo GC25E-3 Specifications

General

Brand	Daewoo
Model	GC25E-3
Category	Engine
Language	English