2. Place the cylinder block on a clean, level work surface, crankcase side up. Wipe the inside surfaces of the main bearing caps and the corresponding recesses in the crankcase with a clean cloth - they should be spotlessly clean.
3. Clean the back of the new bearing shells with a cloth and place them in their working position in the crankcase. Make sure that the mounting tabs on the bushings fit into the corresponding recesses in the crankcase and that the lubrication holes are correctly aligned (see illustration). Do not drive bushings into place with a hammer or other bushing. It is critical not to damage or contaminate the running surfaces of the bearings.
4. Install thrust washers on each side of #4 bearing (5 cylinder engines). Apply a small amount of lubricant to keep the washers in place. Make sure they fit correctly in the grooves, with the lubrication nods facing outwards (see illustration).
5. Wipe the installed main bearing shells and crankshaft journals again with a clean cloth. Make sure that the oil holes in the crankshaft are not clogged, as the grains left here will get on the new liners when the engine is first started.
6. Carefully place the crankshaft into the crankcase, being careful not to dislodge the bearing shells.
Checking the working clearance
7. There must be a gap between the crankshaft and the bearing shells so that the lubricant can circulate. This gap cannot be checked with a feeler gauge, so a special Plastigage tool is required. The tool consists of a scale and plastic threads of round cross section. Proceed as follows.
8. Cut a few pieces of Plastigage slightly shorter than the length of the crankshaft journal. Place a piece on each journal, parallel to the axis of the shaft (see illustration).
9. Wipe the reverse surfaces of the new lower main bearing shells and install them in the caps so that the mounting tabs fall into the corresponding recesses (see illustration).
10. Wipe down the bearing surfaces and, if possible, lightly coat them with silicone repellent to prevent Plastigage from sticking. Install the covers, each exactly in place, using the manufacturer's marks for orientation. The covers must be installed so that the recesses for the mounting tabs of the shells are located on the same side as in the bearing seat.
11. Working from the center bearing cap to the periphery, tighten the bolts by turning them half a turn in one step, with the first stage torque (see specs). Do not move the crankshaft while the Plastigage is under the bushings. Gradually loosen the bearing cap bolts and remove them, being careful not to dislodge the Plastigage.
12. Measure the width of the Plastigage thread using the tool scale (see illustration). This measurement is equal to the operating clearance of the bearing - compare it with the data given in the Specifications. If the gap is out of tolerance, the cause may be foreign particles that have fallen under the liners; try to clear them and check again. If the results are still unsatisfactory, remeasure the neck diameters and check the bearing dimensions. If one end of the Plastigage is thicker than the other, the necks may be tapered and need to be resharpened.
13. If the gap is within specification, carefully remove any remaining Plastigage from the necks and bushings. Use a soft plastic or wooden scraper to avoid scratching surfaces.
Crankshaft - final installation
14. Lift the crankshaft out of the crankcase. Wipe the seating surfaces of the bearings in the crankcase and covers.
15. Lubricate the bearing shells in the crankcase liberally with clean, specified grade engine oil (see illustration).
16. Lower the crankshaft to the operating position so that the connecting rod journal of cylinder No. 1 is at BDC.
17. Lubricate the lower shells in the main bearing caps with clean engine oil, then install thrust washers on both sides of the #3 or #4 bearing cap (depending on the model), bearing in mind that the projections of the washers must fit into the recesses in the bearing cap (see illustrations). Make sure the mounting tabs on the bushings are still in their respective slots in the covers.
18. Install the main bearing caps in the correct order and orientation - the #1 bearing cap should be at the front end of the engine, and the grooves for the mounting tabs of the bearing shells in the seats and bearing caps should be facing the same direction (see illustrations). Insert the bearing cap bolts and tighten them only by hand for now.
19. Moving from the cover of the central bearing to the outer covers, tighten the bolts of their fastening with the tightening force regulated specifications. Where the tightening is divided into several stages, tighten all the bolts with the force of the first stage, then repeat the action in the same sequence for the next stage, etc. (see illustrations).
20. Make sure the crankshaft rotates freely by turning it by hand. If resistance is felt, check the running clearances as described above.
21. Check the crankshaft end play as described at the beginning Chapters 8.
22. Install pistons and connecting rods or connect them to the crankshaft (see chapter 14).
23 See Section 1A and do the following:
- a) Install the crankshaft rear oil seal housing with a new oil seal (Section 1A).
- b) Install the oil pump and suction pipe, sump baffle and sump (Section 1A).
- c) Install flywheel and clutch or drive plate (depending on dress) (Section 1A).
- d) Install crankshaft sprocket and timing belt (Section 1A).
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