Table of contents: Checking cylinder diameters ↓ Checking the clearances between the… ↓ Checking the axial clearance of the… ↓ Checking the dimensions of pistons… ↓
Checking cylinder diameters
Make precise measurements of the cylinder diameters. Use a bore gauge to measure in three zones, both in the transverse direction "A" and in the longitudinal direction "B", as shown in the diagram in the section "Four-cylinder engine"
In cases where wear exceeds the permissible values by more than 0.08 mm, bore the cylinders to the nearest repair size and install pistons of the corresponding repair size.
Checking the clearances between the bearings and the crankshaft journals
Thoroughly clean the working surfaces of the bearings and the corresponding crankshaft journal. Place a piece of plastic calibrated wire equal in width to the bearing on the journal surface.
Depending on the type of journal being checked, install the connecting rod with the cap or the main bearing cap on the journal and tighten the nuts or mounting bolts accordingly. Tighten the connecting rod bolt nuts to a torque of 5.0 kgf·m, and the main bearing cap mounting bolts to a torque of 6.5 kgf·m. Do not allow the engine crankshaft to turn.
Carefully remove the lid and use the scale on the package to determine the gap size by flattening the wire. More detailed information is provided in the accompanying documentation from the manufacturer of the calibrated wire.
The nominal design gap is 0.016-0.075 mm (maximum permissible 0.16 mm) for root and 0.015-0.062 mm (maximum permissible 0.12 mm) for connecting rod journals.
If the gap is greater than the maximum, grind the crankshaft journals to the repair size.
Checking the axial clearance of the crankshaft
Check the axial clearance of the crankshaft using a feeler gauge on the third support, which should be no more than 0.25 mm.
If necessary, achieve the proper clearance by placing thicker thrust washers on the fourth support.
Checking the dimensions of pistons and piston rings
Determine the degree of piston wear by measuring the diameter 10 mm from the edge of the piston skirt perpendicular to the axis of the piston pin. The piston is subject to replacement if its diameter differs by more than 0.04 mm from the permissible values (see subsection "Detailed technical specifications".
Replace piston rings or pistons if the clearances between piston rings and grooves exceed the permissible values (see subsection "Detailed technical specifications").
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