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Service crankshaft and main bearings

To perform the procedures described below need remover (to remove the gear of the crankshaft), micrometer and dial gauge plunger type.

Withdrawal

PERFORMANCE ORDER

With extracted from the vehicle engine, remove the belt gas distribution, oil pan, oil pump maslozabornik, oil pump, flywheel and rear oil seal holder. Remove the spark plug from the engine. Give fixing nuts and remove the cover bottom heads of rods, putting them in order to install the engine. Carefully push the connecting rod and piston assembly up into cylinders, without reaching the upper limit of stroke. Check on rods and covers the connecting rod bearing identification tags. With blade-type probe (the fourth main bearing - see. Accompanying illustration) or a dial gauge, check the axial play of the crankshaft (the meter is fixed on the front wall of the block to the end of the plunger shaft). If you are using a dial gauge push the crankshaft all the way back and reset the device. Push the shaft forward until it stops and read the dial gauge. If the surface of the hard work of the central main bearing are in good condition, the result of measurement should not exceed 0.30 mm. In several steps, loosen the bolts common crankshaft bearing caps, - operates in the reverse order of their tightening. Components common crankshaft bearing caps are shown in the accompanying illustration. Note the location of the long bolts. 1 - Bolts 2 - a cover 3 - bearing shells Before removing the crankshaft is possible to measure the gaps in its main bearings with the help of the calibrated plastic wire set Plastigage: Carefully wipe surfaces with a clean lint-free bearing with a cloth; Place the seven segments of the calibrated measuring wire set along the necks of the shaft (slightly off-axis); Install the crankshaft bearing caps total in diagonal order, moving from the center outwards, tighten bolts of its fastening; Do not twist the shaft after laying him pieces of wire. Give bolts and carefully remove the cover, remove the lower bearing shells; By measuring scale on the packaging of the measuring set width flattened plastic thread segments, identify gaps in the main bearing shaft; Where the wire is flattened more than the gap smaller, and vice versa. Carefully remove the crankshaft from the crankcase of the engine, - try not to damage or dropping the upper main bearing shells, especially if you do not plan to replace them. If inserts to be replaced, remove them from their beds in the crankcase.

Checking the Status

PERFORMANCE ORDER

Assess the degree of deterioration of indigenous and crankpins of the crankshaft, check for the taper and roundness. If necessary, make a groove necks to the nearest standard size repair. Even in the case of wear or damage is only one of the necks (indigenous or crank) must eat through all other (or root or connecting rod). It should prepare a new bearing shells corresponding repair size. If the character does not allow to recover the wear of the shaft journal through the bore, the shaft should be replaced. Check the condition of abutment surfaces of the central bearing (see. Accompanying illustration). In case of deep cavities and workings replace bearing shells, which should lead to normal crankshaft end play. 1 - built-in thrust plates 2 - pad thrust bearing 3 - Main bearing cap Even if the main bearing clearance found to be satisfactory, check inserts for scratches, burrs, cracks, cavities and other defects. If necessary, replace defective pads (in pairs). Place the crankshaft ends in the V-shaped blocks and using a dial gauge, measure the value of its heartbeat in the central main bearing. If the result exceeds 0.10 mm, the shaft should be replaced.

Setting

Installation is in the reverse order.

PERFORMANCE ORDER

Check the patency of all maslotokov and cleanliness of necks of a shaft. Once again, wipe the pads of bearings and lubricate them with pure impellent oil. Properly place the inserts in their beds. When installing the upper main bearing shells Ensure combining oil holes in them with the corresponding holes in the beds. Upper ear distinguished by the presence of oil grooves. Place the crankshaft in the cylinder block, tucking crankpins in the bottom head of his rods. Place the lower main bearing shells in their bed in the lid. Make sure the landing tabs inserts included in the response notches in the lid. Grease the bottom loose leaves of radical bearings with pure impellent oil and establish assembly crankshaft bearing caps to the engine. Screw cap bolts in several stages, tighten them with effort 46 ÷ 52 Nm in the order shown in the accompanying illustration. Make sure the bolts are screwed longer in their previous hole. Check up freedom of rotation of the crankshaft. Measure axial play of the shaft. Replace the crankshaft rear oil seal and replace the unit holder. Put the bottom heads of rods at its shaft journal. Grease connecting rod bearing shells clean motor oil and install the bearing caps on their heads lower rods. Ensure appropriate identification marks of rods and caps. Tighten the connecting rod bearing caps with the required effort. Install all removed in the process of dismantling the components.