Mopar 4556224 Crankshaft

One of the early processes of reassembling the engine is the installation of the crankshaft, supposing the engine block and crankshaft have been washed, checked or mended. Rotate the engine so that bottom is up, then unscrew the main bearing cap bolts and take off the caps; store the caps in the order that they were removed, as a reference for reassembly, the thrust bearings of the 3.0L V6 engine are situated at the no. 3 journal. In the case that the original bearing inserts are still installed, it is necessary to remove the bearing inserts from the blocks and caps and to ensure that the bearing surfaces are absolutely clean and free of lint. Do not apply fingers on the face of the new bearing inserts when installing since oil and acids can easily carve the bearings. Degrease or clean the back sides of the new main bearing inserts and install one in each main bearing saddle in the block with the groove in the direction as indicated on the housing, or in the block; the tab should be located in the recess if equipped with one. The oil holes must match in the block and the bearing inserts and no form of lubrication should be applied at this point. For number 2.5L four cylinder, number 3.0V six cylinder, thrust bearing is installed in number 3 cap and saddle; for number 3.3L and number 3.8L engines it is installed in number 2 cap and saddle. Pressure wash or manually remove any debris in the bearing faces in the block and crankshaft main bearing journals, check and clean or pressure wash oil hole in the crankshaft, if the hole is confirmed to be clear, carefully dropped the crankshaft into the main bearings. Before the housing is finally mounted, one should measure the main bearing oil clearance with the Plastigage and place a piece of it parallel to the axis of the crankshaft main bearing journal on the journals. Scrape off all the bearing faces in the caps and reinstall it where it belongs with the arrow facing front of the engine When tightening the main bearing cap bolt, do it in sequence without turning the crank. When all the bolts have been removed and the main bearing caps lifted off, read off the width of the crushed Plastigage and relate it to the envelop bearing and main bearing oil clearance the reading should be made at the widest part. If the clearance is not as specified, than look between the bearing inserts and caps or block for dirt or oil before going to the next step of ordering different inserts. Clean all the main bearing journals and bearing faces by scraping off very carefully any trace of the Plastigage material. Remove the crankshaft from the engine, and then clean both flat faces of the bearings located in the block and lubricate each bearing and thrust faces with molibase grease or engine assembly lube in a thin layer on each bearings surfaces. It is wise for the crankshaft journals to be free from contaminants before laying down the crankshaft; then clean the faces of bearings in the caps and apply a layer of lubridant. Place the caps back in the same positions with the arrows facing forward, put the bolts on and tighten all the bolts up to the final torque, in a star pattern, starting from the middle and tightening in a star pattern and then tighten the thrust bearing cap bolts to only 10-12 ft-lbs. Knock the ends of the crankshaft with lead or brass hammer to bring into line the main bearing and the crankshaft thrust surfaces, and torque all the main bearing cap screws in a progressive manner starting from the center proceeding outwards in a star pattern, and physically rotate the crankshaft clockwise and anticlockwise to check for binding. Last of all, verify the crankshaft end play with feeler gauges or a dial indicator and it should be correct if the crankshaft thrust faces are not worn or damaged and the bearings are new and the new rear main oil seal has been fitted.

The crankshaft can only be removed after the engine has been taken out of the vehicle, assuming that the flywheel or driveplate, crankshaft balancer/vibration damper, timing chain or belt, oil pan, oil pump, counterbalance shafts (if equipped), and piston/connecting rod assemblies have already been detached. Before removal, check the endplay by mounting a dial indicator with the stem aligned with the crankshaft, touching one of the crank throws. Push the crankshaft to the rear and zero the dial indicator, then pry it to the front and check the reading; the distance moved indicates the endplay. If it exceeds the specified value, inspect the crankshaft thrust surfaces for wear, and if no wear is found, new main bearings should resolve the issue. If a dial indicator is unavailable, feeler gauges can be used by prying or pushing the crankshaft to the front and slipping the gauges between the crankshaft and the thrust main bearing to measure clearance. Check the main bearing caps for markings indicating their locations, which should be numbered consecutively from front to rear; if not, mark them with number stamping dies or a center-punch, ensuring to make the punch marks near one of the bolt heads. Main bearing caps typically have a cast-in arrow pointing to the front of the engine. Loosen the main bearing cap bolts gradually until they can be removed by hand, noting any stud bolts for proper reinstallation. Gently tap the caps with a soft-face hammer to separate them from the engine block, using the bolts as levers if necessary, and take care not to drop the bearing inserts. Finally, carefully lift the crankshaft out of the engine, ideally with assistance due to its weight, and with the bearing inserts in place, return the caps to their respective locations on the engine block and tighten the bolts finger tight.