Installing and checking clearances
Note: This step assumes that the crankshaft is mounted to the engine as described in paragraph 13.
1. As in the case of main bearings. in connecting rods, it is also necessary to provide the necessary clearance for oil circulation. There are two ways to measure the gap, described below.
2. Place the cylinder block in a clean work area, crankcase up. Install the crankshaft with the connecting rod pin of the first cylinder up.
3. The first method is less accurate and consists of installing the connecting rod bearing caps on the connecting rods with the liners installed.
Note: Install covers correctly as described in paragraph 7. The inside diameter of the connecting rod bearing is measured with a bore gauge. If you subtract the diameter of the corresponding washer from the obtained value, you can get the result - the clearance in the connecting rod and bearing.
4. The second method is to apply "Plastigauge", in the same way, in the case of measuring the clearance in the main bearings (see paragraph 13). This method is much more accurate than the previous one. Wipe the necks with a clean, lint-free cloth. Starting from the neck of the first connecting rod, lay out pieces of a plastic rod along them parallel to the axis of the shaft.
5. Pull the connecting rod up to the shaft journal. Make sure that the marks on the cap and connecting rod match, and install the cap.
6. Tighten cap bolts/nuts as directed specifications. without rotating the crankshaft.
7. Remove the cover without rotating the crankshaft. Attach the spatula from the kit "Plastigauge" to the crushed section of the plate, calculate the clearance in the bearing from it. Compare the data obtained with those given in Specifications.
8. If the gaps are out of tolerance, the wrong size bushings may have been installed (or excessively worn old). Make sure no dirt or oil gets under the earbuds when measuring. Check the neck diameter again. If the flattened plastic bar has different widths at the edges, the neck may be tapered. Eliminate the found cause by grinding the neck or replacing the liners.
9. 8 Finishing off, gently scrape off the plastic from the neck or liner surface using a soft scraper - metal can leave delicate scratches.
Final installation of pistons with connecting rods
10. 8 of this stage assumes that the crankshaft and bearing caps are installed as described in paragraph 13.
11. Make sure the earbuds are properly installed. If installing new liners, remove the preservative compound with kerosene. Wipe the earbuds and necks dry with a lint-free cloth.
12. Lubricate the cylinder walls, pistons with rings and shaft journals with engine oil (pic. 15.12, a, b). Arrange the pistons in order. If the connecting rod caps are attached with nuts, wrap them with tape so as not to cause unnecessary scratches when installing into the block.
13. Start installation from the first cylinder. Ensure that the ring locks are correctly wired as described in paragraph 14, squeeze them with a ring compressor (universal "crimping").
14. Insert the piston into the top of the first cylinder. If oil nozzles are installed, try not to damage them when installing the pistons.
15. Make sure the piston is in the correct orientation in the block - the piston head, connecting rod and cover have marks that should be facing the timing belt, as described in paragraph 7.
16. With a wooden hammer handle, lightly hitting the bottom of the piston, push the piston flush with the mating surface of the block (pic. 15.16).
17. Check that the liner has not moved. Lubricate the bearing and neck with clean engine oil. Being careful not to stain the cylinder walls, push the piston down until the liner is aligned with the crankshaft journal. Remove the tape from the bolts if you wrapped them. Lubricate the threaded part of the bolts and the bottom surface of the bolt heads. Install the cover and tighten the bolts / nuts of its fastening "by hand" (pic. 15.17). Make sure the cover is properly oriented - the bushing locks should be on one side, the wombs on the cover and connecting rod should be facing the timing belt. If necessary, refer to the illustrations for paragraph 7.
18. On diesel engines, the piston crowns are treated differently to ensure correct combustion, pistons 1 and 2 are different from pistons 3 and 4. If the pistons are installed correctly, the largest selection for the larger inlet valve of cylinders 1 and 2 should be facing the flywheel / faceplate, the largest selection for the larger inlet valve of cylinders 3 and 4 should face the timing belt. New pistons are numbered:? means piston 1 or 2,? means piston 3 or 4 (pic. 15.18).
19. Tighten the mounting bolts/nuts to the specified torque for stage 1 (pic. 15.19).
20. Tighten the cap bolts/nuts to the angles prescribed for stage 2 (pic. 15.20).
21. Install the remaining three pistons with connecting rods in the same way.
22. Turn the crankshaft by hand. The shaft should rotate freely, without jamming. A little friction is allowed if new parts are installed, but it must be uniform.
Diesel engines
23. If you are installing new pistons, or a new block with pistons and crankshaft, you must measure the protrusion of the pistons above the surface of the block to calculate the required gasket thickness.
24. Turn the block over with the crankcase facing downwards, rest it on wooden blocks. Attach a dial indicator to the block. Install the meter leg on the docking surface and reset the readings. Move the foot to the bottom of the piston No. 1 and smoothly turn the crankshaft until the piston is at TDC. Measure the protrusion of the piston above the surface of the block in this position (pic. 15.24).
25. Repeat the procedure with the rest of the pistons, recording the results
26. If the results differ from piston to piston, take the highest value as a basis and calculate from this the required gasket thickness using the data given in specifications.
27. If you install the old pistons, install a new gasket of the same thickness as the old one.
All engines
28. Finally, install the oil pump and oil pan, baffle plate and sump, flywheel and cylinder head as described in chapter 2A or 2B.
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