4.3.18. Installation of conrod and piston groups on the engine and check of working gaps of conrod bearings
Selection of inserts of conrod bearings
For the majority of the engines installed on cars of the considered models, the Citroyon company inserts of conrod bearings of two sizes are issued: standard, for use in a set with a standard bent shaft and repair, established on a shaft after a pro-point of his necks.
Always it is possible to obtain more detailed information on release of replaceable components in company service centers of the Citroyon company. You make the order of inserts for a guarantee previously having measured diameters of necks of a shaft.
Before installation of conrod and piston assemblies on the engine it is necessary to make check of working gaps in conrod bearings of a bent shaft (see further).
Check of working gaps of bearings
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1. Carefully wipe backs of inserts and their bed in the lower heads of rods and their covers. |
2. Enclose inserts of bearings in the lower heads of rods and their cover, having tracked hit of the directing uvulas in reciprocal deepenings. Try not to touch working surfaces of inserts. If check of gaps of old bearings is made, track that inserts were established strictly on the former places. Check of working gaps in conrod bearings can be made by two methods (see further). |
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3. The first method yields less exact results and demands a pribolchivaniye of covers to the lower heads of rods, undressed on necks of a shaft (see below the subsection "Final Installation of Conrod and Piston Groups", item 6). Inserts at the same time have to be enclosed in the beds. Fix covers of the lower heads of rods by old nuts, having tightened them with the required effort. Further, by means of a nutromer or Columbus equipped with a vernier scale measurement of internal diameters of assembled bearings is performed. Diameter of the corresponding neck of a bent shaft is subtracted from the result received for each of assemblies then. 4. The second method means use of the calibrated plastic wire from the measuring Plastigage set (see Installation of a bent shaft and check of working gaps of radical bearings). 5. Make sure of correctness of installation of inserts in beds of the lower head of a rod and its cover. Wipe conrod necks of a shaft pure неворсящейся with rags. Lay along necks of NMT of cranks which are in provisions the pieces of a plastic wire corresponding on length from measuring set. 6. Put on rods necks, establish to the place of a cover of conrod bearings (be verified with landing marking). 7. Tighten nuts of their fastening with the required effort (see below the subsection "Final Installation of Conrod and Piston Groups", subitem 7 — 8). Try not to displace the pieces of the calibrated wire laid on shaft necks. 8. Without turning rods, uncover and determine the size of working gaps of bearings by extent of flattening of a wire. Measurement of thickness of the flattened-out wire is performed on the scale put on packing to the Plastigage set. 9. If the received results considerably differ from determined by standards, it is necessary to check whether the established inserts are correctly picked up for the size. Make sure also that between backs of inserts and beds of bearings foreign particles did not get. Once again measure diameters of conrod necks of a bent shaft. If width of the flattened-out piece of the calibrated wire from one of the ends is more than from opposite, it is necessary to check the corresponding neck of a shaft for existence of excessive conicity. In case of need replace an insert or give a shaft to a pro-point with a selection of new inserts of the repair size. 10. It is necessary to notice what manufacturers of cars (Citroyon company) does not stipulate the admissible range of sizes of working gaps in conrod bearings. The values given in Specifications are taken as usual for engines of the considered type and they should be considered only as approximate. Detailed information on sizes of working gaps and selection of inserts of conrod bearings can always be received at company car repair shops of the Citroyon company. 11. In conclusion carefully scratch out traces of the flattened-out wire from shaft necks a nail or edge of an old credit card. |
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Final installation of conrod and piston groups
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1. Sleeves of cylinders (at the corresponding complete set) have to be established on the places (see Cleaning and check of a condition of the block of cylinders/case of the engine). The bent shaft laid in the block of cylinders has to be fixed by covers of radical bearings (see Installation of a bent shaft and check of working gaps of radical bearings). 2. Check correctness of landing of inserts of bearings in the beds (see above). If new inserts are established, track that from them traces of the preserving lubricant were completely removed. Use kerosene or other suitable solvent for rubbing of inserts. Dry wipe pure inserts неворсящейся with rags. Wipe with the same rags rods. 3. Grease mirrors of cylinders, pistons and piston rings with pure motive oil. Spread out conrod and piston assemblies as their installation on the engine on a pure working surface. In case covers fasten on heads nuts, wind hairpins with an adhesive tape for the purpose of protection of cylinders and necks of a bent shaft. 4. Begin with installation of conrod and piston assembly of the first cylinder. Make sure that locks of piston rings are deployed the friend in relation to the friend under the correct corners (see Installation of piston rings). Press out rings a mandrel of the special tool. |
5. At the top enter an assembly rod into the first cylinder of the engine. Take care of incidentally not to scratch a cylinder mirror. On petrol engines track that the tag in the form of an arrow was directed to the bottom of the piston towards a GRM drive arrangement, on diesel engines track that the cut in the piston bottom in the form of a shamrock was developed on the block forward (towards installation of an oil filter). Упершись the wooden handle of the hammer in the piston bottom, push his skirt in the cylinder, having densely pressed the tool mandrel which is pressing out rings to the surface of the block. Continuing to press densely a mandrel, push the piston more deeply until its bottom appears aflush with the surface of the block of cylinders interfaced to a head. |
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6. Make sure of correctness of installation in the beds of inserts of the conrod bearing. Plentifully grease a neck of the first crank of a bent shaft and both inserts with pure engine oil. Watching to damaging a cylinder mirror, accurately put on the lower head of a rod the shaft neck given to situation by NMT. 7. Establish a cover of the conrod bearing, then screw fixing nuts and tighten them by hand. Track that identification tags correctly were combined (the directing uvulas of inserts have to rest each other). |
8. Evenly, in stages tighten fixing nuts with effort of the first stage of tightening. |
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Petrol models
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1. Completely weaken both nuts and again tighten, with effort of the second stage this time. Now hold on nuts on a corner of thirds of a stage of tightening, - use a goniometer, or the template which is cut out from a cardboard. |
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Diesel models
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1. Hold on nuts on a corner of the second stage. |
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All models