Selection of liners of main bearings
Attention! The manufacturer recommends changing the main bearings every time the engine is disassembled, regardless of their condition.
1. Spare parts are supplied as standard main bearings of various size groups, as well as overhaul main bearings. Bearings are selected according to the measured diameter of the main journal.
Checking clearances in main bearings
2. Clean the outer surface of the new main bearings, the surfaces of the bearing bores in the cylinder block and the main bearing caps.
3. Insert the liner, make sure that the tab on the bearing shell is in the recess in the bore of the cylinder block or the cover (see photo). The gap can be checked in two ways.
4. When determining the gap in the first way, install the covers (or lid frame) main bearings together with liners on the cylinder block, tighten the bolts to the specified torque and measure the inner diameter of each assembled pair of liners. The clearance in the main bearings is defined as the difference between the diameter of the corresponding crankshaft main journal and the inner diameter of the assembled bearing.
5. The second way (more accurate) consists in the use of a plastic gauge wire.
6. With the main bearings in place, carefully position the crankshaft. The root necks must be dry and clean.
7. Lay one piece of calibration plastic wire parallel to its axis on each main journal of the crankshaft "Plastigage", the length of which is slightly less than the width of the main bearings (see photo).
8. Install the covers with the bottom bushings without disturbing their orientation. Tighten the bolts in the sequence indicated in the Technical data (in 3 stages). During tightening, the position of the wire segment should not change, the rotation of the crankshaft is not allowed. Loosen the cover bolts evenly and gradually. Remove covers (or frame), without disturbing the position of the flattened wires and preventing the crankshaft from turning. Compare the width of the crushed wires with the scale on the package and determine the clearance in the main bearing (see photo). Compare with standard value.
9. If the gap differs from the standard, then the reason may be the wrong selection of liners (or their increased wear if used liners were checked). If the width of the flattened wire from one edge is greater, then this indicates a tapered neck. Before concluding that the bearings need to be replaced, make sure that there is no dirt or oil between the covers or the cylinder block and the bearing when measuring.
10. If, when measuring with new liners, the gap exceeds the norm, then you should seek advice from a car service. It may be necessary to regrind the crankshaft journals and replace the liners with repair ones.
11. When finished, scrape off the remnants of the calibration wire from the crankshaft main journals without damaging the surface.
Final installation of the crankshaft.
Engines 1.4, 1.6 and 1.8 liters
12. Carefully remove the crankshaft from the cylinder block.
13. Establish on a place loose leaves of radical bearings. If new bearings are fitted, wash them thoroughly in kerosene and wipe dry. Liberally lubricate the surfaces of the liners installed in the cylinder block with fresh engine oil (see photo).
14. Install the crankshaft in the cylinder block and check the axial play (see above).
15. Carefully clear from greasing split planes of covers of radical bearings and the block of cylinders. Lubricate the surfaces of the lower bearings with engine oil. Make sure that the mounting tabs on the bushings fit into the recesses in the covers.
16. Replace covers numbered 1-4 (Thrust flanges are provided on liners of the 3rd cylinder), guided by the applied numbers (numbers must face up and read from the rear of the cylinder block).
17. Fill the grooves of the 5th main bearing cap with sealant (see photo). The manufacturer recommends using OPEL sealant 9048525. Install the cover in place.
18. Lubricate the cover bolts and tighten by hand (see photo).
19. Tighten the cap bolts diagonally in 3 steps (see technical data).
20. After tightening the bolts, add sealant to the groove of the 5th bearing cap (see photo). Cover groove must be filled with sealant (sealant should come out from under the joints). Remove excess sealant with a rag.
21. Check the freedom of rotation of the crankshaft in the main bearings.
22. Install connecting rods with pistons (see below).
23. Install a new rear oil seal
24. Install the flywheel, cylinder head, oil pump, oil deflector, under the bottom and camshaft belt.
Engine 2.0L
25. Establish the crankshaft in the order considered above.
26. Install the balance mechanism (or lid frame), tighten the bolts to the specified torque
27. Install a new rear oil seal, flywheel, cylinder head, oil pump, oil deflector, sump and camshaft belt.
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