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Service connecting rod and piston assembly and the cylinder bores

To perform the procedures described below require the following special equipment: countersink to remove the stepped cylinder wear; micrometer and telescopic bore gauge (to check the condition of the cylinder); khon (to restore cylinder bores) and tools for the expansion and contraction of the piston rings (for mounting and installing connecting rod and piston assemblies).

Removing the connecting rod and piston assembly

In principle, the removal of connecting rod and piston assembly can be done without removing the engine from the car, but when you take into account the difficulties involved in removing the sump and the work under the vehicle, such an approach does not seem appropriate. The drafters of the Guidelines recommend doing the work on the engine is removed from the car.

Components connecting rod and piston assembly shown in the accompanying illustration.

1 - lower compression ring 2 - upper compression ring 3 - upper section of oil scraper ring 4 - expander oil ring 5 - lower section of the oil scraper ring 6 - piston 7 - piston pin 8 - rod 9 - bearing shells 10 - cover 11 - Nuts

PERFORMANCE ORDER

Remove the engine from the car. Mount the motor on the mounting stand or a sturdy workbench and remove the cylinder head, oil pan and oil pump maslozabornik. Make available identification labels on the bottom heads of rods and connecting rod bearing caps of the crankshaft. Try to remember how to install assemblies. With the probe blade type Check the axial clearance of rods. If you exceed the allowable backlash (see. Table sizes and adjustments in the end of this manual), replace worn rod. Citing the first cylinder to the bottom of its stroke, give the nuts cover the bottom head of a rod (rod bearing). Remove the cover. Clean the bearings in the cover and the open part of the crank pin shaft clean lint-free cloth, then lay along the cervical segment of the calibrated plastic wire measuring set Plastigage. Put the cap on the connecting rod and tighten nuts of its fastening with demanded effort. Remove the nut, remove the lid and measuring scale on the packaging of the set width of the flattened plastic thread, determine the amount of connecting rod bearing clearance. Compare result of measurement with the regulatory requirements (see. Table sizes and adjustments in the end of the Guidelines), in excess of the allowable limit, replace the bearing assembly. Repeat for the remaining rods. Note the value of each of the bearing clearance. Alternately, remove the covers of the bottom heads of rods and then push out the wooden handle of a hammer assembly of the cylinder through the top, and then immediately install the rods their covers with embedded inserts. To protect the crankshaft journals and the cylinder bores from damage during the extraction process connecting rod and piston assembly put on the bearing cap bolts lengths of plastic tubing. If necessary, before embarking on a recovery connecting rod and piston assembly should be using the special countersink to remove the step wear at the top of the cylinder. Remove the pistons (over the top), piston rings and discard them.

Checking the pistons

PERFORMANCE ORDER

Inspect the pistons for signs of response, scratching, scuffing and burnouts. Remove all traces of carbon deposits from the bottom of the piston and of the annular groove. Please rate the degree of deterioration of piston ring grooves. To this end, taking the new Measure, check the magnitude of backlash in the respective grooves of each of the pistons (see. Accompanying illustration). Compare result of measurement with the regulatory requirements (see. Table sizes and adjustments in the end of this manual). Inspect the connecting rod bearing shells all pistons at identifying signs of wear. If you find elaboration outer edges of the inserts should check the appropriate rod to bend. As for the straightening rods special equipment is required, the drafters of this Guide recommends this test and refurbishment of producing in the studio Car.

Checking the status of the block and cylinder bores

PERFORMANCE ORDER

Check the mirror cylinders for cracks, burrs, scratches and operation. Using a special callipers complete with a micrometer, measure the diameter of the cylinder in order to assess their degree of wear and detection of roundness and taper. Measurements are made in both directions (up and down the block) and at three levels of height of the cylinder - at the upper end of the stroke, the middle and the bottom. The difference between the distances A and B (see. Accompanying illustration), measured from the top and bottom edges of the stroke determines the roundness of the cylinder, the difference between the measurements and the upper and lower planes of the working area of the cylinder determines the taper. From the results of the six dimensions of each of the cylinders, select the maximum and minimum readings. The difference between these readings can be considered as a criterion the degree of wear of the cylinder. If deterioration of any of the cylinders exceeds the limit (see. Table sizes and adjustments in the end of the Guidelines) should be pierced all cylinders to a standard repair size (in excess) and their subsequent honing. Selecting the size of the maintenance of specified standard is determined by the size of the most heavily worn cylinder. Using the meter and probe the flatness of the blade type, check the flatness of the upper mating surface of the block (Proceed as for checking the flatness of the cylinder head). If the flatness unit exceeds the limit (see. Table sizes and adjustments in the end of this manual), remove the crankshaft, install the unit cover gas distribution chain and a groove assembly. Thoroughly flush the unit with a suitable solvent and dry it with compressed air, paying particular attention to flushing maslotokov and inaccessible cavities. Inspect the unit for cracks and other mechanical damages.

Honing of cylinder bores

Mirror cylinder suitable for use in a kit with the old pistons, but requiring replacement of piston rings to be honed.

PERFORMANCE ORDER

For removal of polishing cylinder bores use Hon surface with 280-grit grinding stones. Slide rotating nozzle hone up and down in the cylinder at a rate to achieve a mesh pattern cuts with an angle of intersection of 60 ?� scratches. Such processing ensures optimal conditions for the running of the piston rings. It should not be removed from the cylinder bore more material than is necessary for the removal of polishing, since otherwise there will prohibitive cylinder diameter and hence the piston gap. During the processing nozzle and lubricate the cylinder wall special honingovochnym oil. Using the transmission or motor oils as well as mineral spirits and kerosene for this purpose is unacceptable! At the end of honing cylinders carefully wipe the mirror, completely removing all traces of them from the abrasive. After washing and drying the block once again wipe the mirror clean lint-free cloth cylinders, then lubricate motor oil to prevent the development of corrosion.

Check piston clearance

PERFORMANCE ORDER

With high-quality bore gauge and micrometer to measure the diameters as described above all cylinders. Measure the diameter of the piston at a distance of approximately 20 mm (A) on an accompanying illustration) of the lower edge of the skirt. Deducted from the corresponding cylinder bore diameter of the piston, the piston define a gap. If the calculation results exceed the permissible values (see. Table sizes and adjustments in the end of this manual), at its discretion, replace or pierce the piston and cylinder othoninguyte. When the cylinder bore size to standard maintenance and honing them repeat the procedure for determining the piston clearance.

If the piston, piston pin and connecting rod must be replaced, it should be done in a workshop service center, having at their disposal the necessary tools and hydraulic presses (for removal and installation of piston pins).

Replace piston rings

PERFORMANCE ORDER

Pick up a set of new piston rings corresponding to your standard size cylinders of the engine of your car (or standard or oversize). Alternately refuel each ring bottom inverted piston in the least worn part of the cylinder to measure the gaps in their castles. Using the piston rings for refilling the cylinder allows for perpendicular arrangement of the ring. After removing the piston measure a backlash in the ring lock using a probe-type blade. After measuring the gap in the lock ring must be used to complete this particular cylinder piston. In accordance with Annex complete with a set of instructions put on the new rings on the respective pistons. Use mandrel-expander piston rings. Rings should be set up labels (to the bottom of the piston). Top, according to the instructions, install the chrome ring. Expand the lock ring on the piston as shown in the accompanying illustrations, where: A = the upper compression ring, B = lower compression ring, C = extender oil ring, D = the upper section of the oil scraper ring, E = the lower section of the oil scraper ring. Said front arrow mark

Installing the connecting rod and piston assembly

PERFORMANCE ORDER

Lubricate the piston assembly and the cylinder wall of the first clean motor oil. Having turned the crankshaft, are the first crank pin of the crankshaft position BDC. Wipe the cervix with a clean cloth, then lubricate it with clean motor oil. Uncover the lower connecting rod bearing shells and wipe, or replace them as needed. Grease the mold is clean motor oil. Put on the cover bolts pieces of plastic tube to protect the walls of the cylinder and the shaft journal. Compress piston rings with special tool, then fill the crank assembly in the first cylinder, tapping the handle of a hammer in the bottom of the piston and at the same time directing the head of the connecting rod on a neck of the connecting rod bearing of the crankshaft. The piston has to wind up in front of the mark on the cylinder head (see. Accompanying illustration) forward on the engine. Tool mandrel for compressing the piston rings must tightly pressed against the unit around the perimeter at all times during installation of the crank assembly (see. Accompanying illustration). Remove the cover bolts to the bottom head of a rod protective plastic tube. Put on the head of the connecting rod bearing cap, watching combining inflicted during dismantling landing labels. Tighten fixing nuts with demanded effort. Operating in a similar manner, the connecting rod-piston assembly in the remaining (corresponding) cylinders. The further installation is made in the reverse order of removal.