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Installation of a cranked shaft and check of backlashes of radical bearings

If during the engine overhaul was conducted groove connecting rods and main journals of the crankshaft to the standard size of the repair (with belittling 0.254 mm), the choice of replacement bearings should not cause difficulties. It is easy to order the same standard set of inserts of the repair size. However, it should be remembered that even in cases where the bore of the shaft and replace the bearings before you start assembling the motor needs to check the clearances in the bearings. (see. p. "Regardless of the method used ...").

On the factory assembly line engine size necks mounted shaft and bearing may vary slightly. The crank and bearings are usually marked color code that allows to determine the correct matching inserts the shaft journal. If the motor is installed standard size crankshaft, the selection of new bearings may be implemented in accordance with the materials of the section Checking the engine block. If necessary, expert advice is always available in the garage, which specializes in the restoration of engines.

The color code is usually stamped on the edge of the bearing.

The code size of the neck usually is put paint on her cheek nearest the crank side with flange (rear) end of the shaft. The only exception is the neck rear main bearing, the code for which is applied to the flange of the rear crank 6-cylinder engines. On the V8 engines in the rear flange of the crankshaft applied alphanumeric code size of the necks (see. Section Checking the engine block).

In order to make fine adjustments to the gap upper and lower flanges of the bearing can be adjusted in different sizes. For example, to reduce the gap to 0.0127 mm nominal size insert can be installed in combination with a second size with belittling to 0.0254 mm.

In no event should not be installed in the one bearing inserts that differ by more than 0.0254 mm. Inserts gypsy size should always be installed either all up or all down.

Measurement of backlashes in radical bearings

Regardless of the method used for determining the amount the bearing, a gap therein should be checked with a special set of plastic wire with a calibrated (Plastigage). Such checking ensures the correct selection of loose leaves.

PERFORMANCE ORDER

Wipe the back of the new main bearing shells and place one equipped with an oil groove in each of the beds in the unit. The second half of each of the sets of inserts put into the appropriate cover. Make sure that the tabs inserts includes responses recess in the block or the lid. Oil holes in the block must be aligned with the holes in the liner. In no case do not insert zastukivaet hammer to bed and try not to scratch the surface of the bearing and leave them scoring. Lubrication at this stage should not be produced. Wipe the surface of the bearing block and crankshaft journals clean lint-free cloth. Check the permeability and, if necessary, clean all the oil hole of the shaft. Dirt are inevitably get into the bearing. Upon being impeccably clean the crankshaft and carefully lower it into the main bearings. Before final installation of the shaft is necessary to make a measurement of the gaps in its main bearings. Cut into pieces of the appropriate length (slightly shorter than the length of the main journals of the shaft) Gauging Plastic Plastigage from a set and place one along each of the main journals of the shaft parallel to its axis. Lay on the segment of the calibrated plastic wire measuring set along the axis of each of the main journals of the shaft, parallel to its axis. Wipe the surface of the bearings in the cover and install the latest on the places in the unit (do not confuse the cover) so that the cast on top of their arrows are facing forward on the engine. Be careful not to dislodge laid on the neck of the shaft lengths of wire. Lightly oil the bolt bearing caps, screw bolts. The three stages tighten bolts of covers with demanded effort. Do not turn the shaft in the process of tightening the bolts. Give bolts and carefully remove the bearing caps. Put them in the same order as they were installed on the engine. Try in removing covers not displace the flattened pieces of wire and crank. If any of the covers are not amenable to removal, gently Tap the its hammer with soft brisk. Measure the width of the flattened plastic thread segments using the scale on the package to the test set. The result is a direct measurement of the magnitude of the gap in the bearing. Compare results of measurements to requirements of Specifications. When collation of the results of trace for compliance scale standard specifications Specifications - on the package applied two scales - one in the US (inch) standard, the second - in the metric. Measure the width of the flattened plastic thread segments on each of the necks of the shaft on a scale on the package to the measuring set (measurement is made in the widest part of the segment). If the clearance does not comply with the Specifications may set inserts wrong size (which means that the selection of a replacement). Before coming to the conclusion about the need to replace the inserts make sure that between their backs and the bed covers or bearing block during the measurement gap were not dirt or oil. If the wire is flattened calibrated widely from one of the edges of the neck, the latter has a taper. Carefully scrape off from the surfaces of the necks and / or bearing all traces of flattened plastic wire. Use for this purpose a fingernail or credit card edge - the presence on working surfaces of bearings burrs and burrs unacceptable!

Final installation of the crankshaft

PERFORMANCE ORDER

Carefully remove the crankshaft of the engine. Sand the surface of the bearing block and lubricate them with a thin layer of molybdenum or a uniform assembly lubricant. Coat the surface of the crankshaft seals in contact with clean motor oil. Set in the upper half of the block back radical epiploon (marked with yellow paint on the back side of the engine (V8), and sealing jaws - forward. Insert into the groove of the top half of the block neoprene rear crankshaft oil seal ... ... Sponges (arrow) down the engine. Make sure that the crankshaft journals are clean and place the shaft in the block. Wipe the surface of the bearing caps and lubricate them. Install the cover into place so that the arrows are pointing in the forward engine. Install bolts, having greased their carving and the bottom part of the head with oil. Put them on each side of the mating surface of the cover on the rear main bearing spot sealant Locktite 515 (point of application of the sealant to the crankshaft bearing caps V8 engine cm. In the to Chapter Engine V8). In the figure marked portions of the surface cover of the back radical bearing a 6-cylinder engine, apply sealant Locktite 515. Put the bottom half of the gland in the rear main bearing cover and replace the cover to its place on the block. Fit the bottom half of the new neoprene oil seal in rear crankshaft bearing cap. Tighten bolts of all covers, except for the cover of the thrust bearing (?�� 3), with the required effort. Gently move the crankshaft lever back and forth in a block, then tighten the bearing cap bolts third with demanded effort. Check axial play of the shaft using a probe or a digital meter plunger type (Section Removing the crankshaft). The axial clearance must lie within acceptable limits if the surface of the shaft bearings are not worn or damaged and installed new bearings. On models equipped with Manual transmission, set on a pin shaft new guide bearing (Chapter Clutch and transmission line). Several times a cranked shaft, making sure that there are no obvious sticking points.