Reasons for bearing wear
1. Reducing the tensile strength of the metal; jagged scratches
2. Improperly planted; bright (polished) stripes
3.Scratched by dirt; dirt has penetrated the surface
4. Lack of oil; worn top layer
5. Excessive wear; the top layer is wiped off over the entire surface
6. The bearing is deformed; the top layer is wiped off in a circle
Although the old bearing shells are replaced with new ones when the engine is overhauled, the old bearing shells must be carefully inspected. Inspection of the liner can reveal the cause of its wear.
Bearing failure occurs due to lack of lubrication, the presence of dirt and other foreign particles, motor overload and corrosion. In any case, the cause of damage to the bearings must be eliminated before assembling the engine.
Insert selection
For the correct selection of liners, be guided by the size of the lubrication gap, which can be measured using a plastic measuring tape. If you have any problems with the selection of liners, contact the specialists.
Main bearings
Dimensions required to determine the thickness of the main bearing shells (4-cylinder engines)
Main bearing dimensions for 4-cylinder engines are stamped on the mating surface of the oil pan and on the cylinder block (A), the dimensions of the journals of the main bearings are stamped on the counterweight of the crankshaft (IN). On 6-cylinder engines, the bearing dimensions are stamped on the cylinder block above the crankshaft, and the bearing journal dimensions are stamped on the first crankshaft counterweight.
By adding the corresponding numbers on the block and on the crankshaft, you will get the required bearing size for a four-cylinder engine. To select liners for six-cylinder engines, use the table.
Sum | |||||
The number on the cylinder block (A) plus the number on the crankshaft (IN) | 0 – 5 | 6 – 11 | 12 – 17 | 18 – 23 | 24 – 28 |
Use insert N | 3 | 4 | 5 | 6 | 7 |
Example: Cylinder block number 06 + crankshaft number 08 add up to 14 - use bushing N5.