Big-end bearing play, check (check bearing play with a micrometer and internal measuring instrument)
Big-end bearing play, check (check bearing play with a micrometer and internal measuring instrument) |
Note | ||
Connecting rod and crankshaft are removed. |
Big-end bearing cap together with big-end bearing shell on the connecting rod - tightening torque 25 Nm + 30°.
The bolts can be used one more time for checking the big-end bearing play.
Equation for calculating average big-end bearing diameter: | I + II + III |
3 |
Example: | ||
I | 42.738 mm | |
II | 42.732 mm | |
III | + 42.741 mm | |
128.211 mm | divided by 3 = 42.737 mm |
Average big-end bearing diameter is 42.737 mm.
The average big-end journal diameter is measured using a micrometer at positions I and II and then calculated.
Equation for calculating average big-end journal diameter: | I + II |
Big-end journal diameter | 2 |
Example: | ||
I | 42.729 mm | |
II | + 42.725 mm | |
84.454 mm | divided by 2 = 42.727 mm |
Average big-end journal diameter is 42.727 mm.
The big-end journal play is calculated using the different diameters of the big-end bearing hole and the big-end journal.
Example: | |
Average big-end bearing diameter | 42.737 mm |
Average big-end journal diameter | - 42.727 mm |
0.010 mm |
Permitted big-end bearing play: 0.019 to 0.071 mm.