ENGINE
B1220, B1620, B1820, WSM
1-S4
(EU)
2. SERVICING SPECIFICATIONS
ENGINE BODY
Item Factory Specification Allowable Limit
Valve Clearance (Cold) 0.145 to 0.185 mm
0.00571 to 0.00728 in.
–
Compression Pressure
• Difference among Cylinders
2.84 to 3.24 MPa
29.0 to 33.0 kgf/cm
2
412 to 469 psi
–
2.26 MPa
23.0 kgf/cm
2
327 psi
10 % or less
Top Clearance 0.50 to 0.70 mm
0.0197 to 0.0276 in.
–
Cylinder Head Surface Flatness – 0.05 mm
0.002 in.
Valve Recessing Intake and Exhaust −0.10 to 0.10 mm
−0.0039 to 0.0039 in.
0.30 mm
0.0118 in.
Valve Stem to Valve Guide
• Valve Stem
• Valve Guide
Clearance
O.D.
I.D.
0.030 to 0.057 mm
0.00118 to 0.00224 in.
5.968 to 5.980 mm
0.23496 to 0.23543 in.
6.010 to 6.025 mm
0.23661 to 0.23720 in.
0.10 mm
0.0039 in.
–
–
Valve Face Angle 0.785 rad
45 °
–
Valve Seat Angle
Width
0.785 rad
45 °
2.12 mm
0.0835 in.
–
–
Valve Spring Free Length
Tilt
Setting Load /
Setting Length
31.3 to 31.8 mm
1.232 to 1.252 in.
–
64.7 N / 27.0 mm
6.6 kgf / 27.0 mm
14.6 lbf / 1.063 in.
28.4 mm
1.118 in.
1.2 mm
0.047 in.
54.9 N / 27.0 mm
5.6 kgf / 27.0 mm
12.3 lbf / 1.063 in.
Rocker Arm Shaft to Rocker Arm
• Rocker Arm Shaft
• Rocker Arm
Clearance
O.D.
I.D.
0.016 to 0.045 mm
0.00063 to 0.00177 in.
10.473 to 10.484 mm
0.41232 to 0.41276 in.
10.500 to 10.518 mm
0.41339 to 0.41410 in.
0.15 mm
0.0059 in.
–
–
Push Rod Alignment – 0.25 mm
0.00988 in.