1225 / 1588
ENGINE
26
VALVE:
Description
Inlet
Exhaust
Valve seat angle on valve
45
0
+ 10'
45
0
+ 10'
Valve head diameter – 'A'
mm 44.10/43.90
36.10/35.90
Valve seat dia on valve – 'C'
mm 42.01/41.99
34.01 /33.99
Valve stem diameter – 'E'
mm 8.950/8.935
9.940/9.925
Valve seat width – 'D'
mm 3.5/2.8
4.2/3.5
Length of valve
mm 140.7/140.3
140.7/140.3
Tappet clearance
mm 0.20
0.30
Cold or moderately warm engine cooling
system temp. 50
0
max.
Permissible runout between valve seat and stem
mm 0.03
0.03
Permissible runout between valve head and stem
mm 0.2
0.2
Permissible ovality of valve seat
mm 0.01
0.01
Minimum thickness of valve 'B' head
mm 2.1
2.1
Hardness of valve on stem end
HRC 57 + 3
57 + 3
Distance between narrow dia of valve face to contact line
mm 0.5
0.5
Distance of valve head to cyl. head parting surface
mm 1.2-1.7
1.2-1.7
VALVE TIMING:
Fig. 7.
Inlet opens
Before TDC
29
0
Inlet closes
After BDC
55
0
53'
Exhaust opens
Before BDC
53
0
58'
Exhaust closes
After TDC
20
0
51'
Fig. 6
Fig. 7
INLET OPENS
29
0
before T.D.C
EXHAUSTCLOSES
20
0
51’ after T.D.C.
T.D.C.
INLET OPENS
55
0
53’ after B.D.C
B.D.C.
EXHAUSTOPENS
53
0
58’ before B.D.C