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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.