Pistons
Pistons |
General data |
Engine
|
|
B204i/B204L/B204E/B204R
|
B235R(Viggen)
|
Mean piston velocity at 5000 rpm (m/s)
|
13
|
15
|
Important | ||
Pistons of different manufacture must not be used in the same engine. The name of the piston manufacturer is cast inside the piston. |
||
Piston types |
Engine
|
|
R
|
|
A
|
H
|
|
B204i
|
mm
|
55
|
42.3
|
4.4
|
68.3
|
|
B204L
|
mm
|
150
|
70
|
4.4
|
68.3
|
|
B235R
|
mm
|
50
|
70
|
3.8
|
56.9
|
Classification of pistons and cylinder bores |
The piston classification is stamped on the piston crown roof. Piston classifications for service are:
AB
B
C
The cylinder classification is stamped on the cylinder face and is specified for each cylinder. The cylinder classifications are:
A
B
B+
They can all occur in the same cylinder block.
Piston classification |
B204
|
B235 (Viggen)
|
||
Standard A (not a spare part)
|
mm
|
89.971 - 89.980
|
89.966 - 89.975
|
Standard AB
|
mm
|
89.980 - 89.989
|
|
Standard B
|
mm
|
89.989 - 90.000
|
89.975 - 89.984
|
Standard C
|
mm
|
90.000 - 90.013
|
|
1st oversize (0.5)
|
mm
|
90.472 - 90.488
|
90.475 - 90.484
|
2nd oversize (1.0)
|
mm
|
90.972 - 90.988
|
90.975 - 90.984
|
Piston clearance, nominal
|
mm
|
0.011 - 0.040
|
0.025 - 0.044
|
Classification, piston/cylinder
|
|
Clearance
|
|
|
|
|
|
A/A
|
mm
|
0.020 - 0.041
|
0.031 - 0.069
|
AB/A
|
mm
|
0.011 - 0.032
|
|
AB/B
|
mm
|
0.014 - 0.040
|
|
B/B
|
mm
|
0.006 - 0.031
|
0.031 - 0.069
|
B/B+
|
mm
|
0.011 - 0.041
|
Piston diameter |
Piston diameter is measured at right angles to the gudgeon pin hole, 9.3 mm (B204L) or 11 mm (B204i) from the bottom edge of the piston.
Piston rings |
|
|
Upper compression ring
|
Lower compression ring
|
Oil scraper ring
|
Thickness B204
|
mm
|
1.728 - 1.740
|
1.475 - 1.490
|
- 2.500
|
Thickness B235
|
mm
|
1.475 - 1.490
|
1.978 - 1.990
|
2.976 - 3.052
|
Side clearance in groove B204
|
mm
|
0.050 - 0.082
|
0.040 - 0.072
|
|
Side clearance in groove B235
|
mm
|
0.020 - 0.065
|
0.040 - 0.075
|
|
Working gap in cylinder B204
|
mm
|
0.30 - 0.50
|
0.15 - 0.65
|
0.38 - 1.40
|
Working gap in cylinder B235
|
mm
|
0.300 - 0.500
|
0.300 - 0.500
|
0.260 - 1.020
|
Gudgeon pins |
|
|
B204
|
B235
|
Diameter
|
mm
|
23.996 - 24.000
|
23.996 - 24.000
|
Clearance, gudgeon pin/connecting rod bush
|
mm
|
0.005 - 0.014
|
0.012 - 0.021
|
Length
|
mm
|
68
|
63
|