Chrysler 4621917 Crankshaft

The crankshaft can only be removed after the engine has been taken out of the vehicle, assuming that the driveplate, crankshaft pulley, timing belt, oil pan, oil pump body, oil filter, and piston/connecting rod assemblies have already been detached. For V6 engines, the rear main oil seal retainer must be unbolted and separated from the block prior to crankshaft removal. First, measure the endplay by mounting a dial indicator aligned with the crankshaft and touching its end. Pry the crankshaft to the rear and zero the dial indicator, then pry it to the front and check the reading; the distance traveled indicates the endplay. If it exceeds the tolerance, inspect the crankshaft thrust surfaces for wear after removal, and if no wear is found, new main bearings should resolve the endplay issue. If a dial indicator is unavailable, feeler gauges can be used by prying the crankshaft to the front and inserting the gauges between the crankshaft and the thrust bearing or washer to measure clearance. Next, loosen the main bearing cap assembly bolts a quarter turn at a time until they can be removed by hand. Gently tap the main bearing cap assembly with a soft-face hammer around its perimeter and pull it straight up off the cylinder block. For 2.0L four-cylinder engines, remove the oil filter passage O-ring seal and the three main bearing cap assembly locating dowels, taking care not to drop the bearing inserts if they come out with the assembly. Finally, carefully lift the crankshaft out of the engine, ideally with assistance due to its weight and awkwardness. With the bearing inserts in place inside the engine block and main bearing caps, reinstall the main bearing cap assembly onto the engine block and tighten the bolts finger tight, ensuring that on V6 models, the assembly is installed with the arrow facing the front (timing belt end) of the engine.

Remove all burrs from the crankshaft oil holes using a stone, file, or scraper. Clean the crankshaft with solvent and dry it with compressed air if available, ensuring the oil holes are cleaned with a stiff brush and flushed with solvent. Check the main and connecting rod bearing journals for uneven wear, scoring, pits, and cracks. Rub a penny across each journal several times; if copper transfers to the journal, it indicates the surface is too rough and requires regrinding. Inspect the rest of the crankshaft for cracks and other damage, and have it magnafluxed to reveal hidden cracks. Measure the diameter of the main bearing and connecting rod journals with a micrometer, comparing the results to the tolerances, and check for out-of-roundness and taper by measuring at various points around each journal's circumference. If the journals are damaged, tapered, out-of-round, or worn beyond limits, regrinding by an automotive machine shop is necessary, along with obtaining and installing the correct size bearing inserts if reconditioned. Examine the oil seal journals at each end of the crankshaft for wear and damage; if a groove is present or if the journal is nicked or scratched, the new seal may leak upon reassembly. In some cases, an automotive machine shop may repair the journal by pressing on a thin sleeve, but if repair isn't feasible, a new or different crankshaft must be installed.