Pistons
| Pistons |
| General data |
|
|
|
B205
|
B235
|
|
Mean piston speed at 5000 rpm
|
m/s
|
13
|
15
|
| Important | ||
|
Different makes of piston must not be fitted in the same engine. |
||
| Control values, pressure |
|
|
|
B205
|
B235
|
|
Compression ratio
|
|
9.3:1
|
9.3:1
|
|
Compression, maximum variation between cylinders
|
bar
|
2.0
|
2.0
|
| Piston types |
|
Engine
|
|
R
|
ΓΈ
|
A
|
H
|
|
B205
|
mm
|
103
|
49.4
|
3
|
57.6
|
|
B235
|
mm
|
190.5
|
80.9
|
4.35
|
56.9
|
| Classification of pistons and cylinder bores |
The piston classification is stamped on the piston crown roof. The piston classes for service are B
First oversize (+0.5)
Second oversize (+1.0)
| Piston classification |
|
Standard A (not a spare part)
|
mm
|
89.951 - 89.969
|
|
B
|
mm
|
89.971 - 89.989
|
|
First oversize (+0.5)
|
mm
|
90.451 - 90.469
|
|
Piston clearance, nominal
|
mm
|
0.031 - 0.069
|
| Piston diameter |
Piston diameter is measured at right angles to the gudgeon pin hole, 11 mm (B205 and B235) from the bottom of the piston skirt.
|
Classification, piston/cylinder
|
|
Clearance
|
|
A/A
|
mm
|
0.031-0.069
|
|
B/B
|
mm
|
0.031-0.069
|
| Piston rings |
|
|
|
Upper
compression ring |
Lower
compression ring |
Oil scraper ring
|
|
Thickness
|
mm
|
1.475 - 1.490
|
1.475 - 1.490
|
- 2.500
|
|
Side clearance in groove
|
mm
|
0.020 - 0.065
|
0.040 - 0.075
|
|
|
Working gap in cylinder
|
mm
|
0.300 - 0.500
|
0.300 - 0.500
|
0.260 - 1.020
|
| Gudgeon pins |
|
Diameter
|
mm
|
23.996 - 24.000
|
|
Clearance, gudgeon pin/connecting rod bush
|
mm
|
0.012 - 0.021
|
This project is supported by memberships and donations. If you use this site, please consider Joining SCNA and/or making a donation.
Our Friends
