7.21. Installation of pistons with rods
Choice of connecting rods
FOUR-CYLINDER PETROL ENGINES
For determination of the required thickness of new connecting rods it is necessary to measure the internal diameter of the conrod bearing, diameter of a conrod neck of a bent shaft and to consider a working gap of the bearing. The required thickness of the bearing can be calculated as follows.
Example
Diameter of the bearing is 62,51 mm
Diameter of a neck of the crankshaft of 57,95 mm
4,56 mm
Working gap of the bearing of-0,04 mm
4,52 mm ±2
2,26 mm
As spare parts inserts of radical bearings of the following thickness are delivered.
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Inserts
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Insert thickness
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Nominal
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1,80 mm
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Repair size 1
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1,92 mm
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Repair size 2
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2,05 mm
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Repair size 3
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2,18 mm
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Repair size 4
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2,30 mm
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SIX-CYLINDER PETROL SOHC ENGINES
Thickness of inserts of conrod bearings is defined in the same way, as well as for 4-cylinder petrol engines. For determination of the required size of inserts it is necessary to consult at the dealer of Mercedes-Benz.
SIX-CYLINDER PETROL DOHC ENGINES
For determination of the required thickness of new connecting rods it is necessary to measure the internal diameter of the conrod bearing, diameter of a conrod neck of a bent shaft and to consider a working gap of the bearing. The required thickness of the bearing can be calculated as follows.
Example
Diameter of the bearing is 62,51 mm
Diameter of a neck of the crankshaft of 57,95 mm
4,56 mm
Working gap of the bearing of-0,04 mm
4,52 mm ±2
2,26 mm
Determine the required thickness of an insert of the radical bearing by the table after consultation with the dealer of Mercedes-Benz.
DIESEL ENGINES
It is necessary for determination of the required thickness of new connecting rods engines. For determination of the required size of inserts it is necessary to consult at the dealer of Mercedes-Benz.