GM 96055086 Engine Crankshaft

The crankshaft can only be removed after the engine has been taken out of the vehicle, assuming that the flywheel or driveplate, crankshaft pulley, timing belt, oil pan, oil pump, and piston/connecting rod assemblies have already been detached. Before removing the crankshaft, check the endplay by mounting a dial indicator with the stem aligned with the crankshaft and 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 to determine the endplay. If the endplay exceeds specifications, inspect the crankshaft thrust surfaces for wear; if no wear is found, new thrust 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 bearing's front face to measure clearance. Check the main bearing caps for markings indicating their locations, ensuring they are numbered consecutively from front to rear; if not, mark them accordingly. 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, lift the crankshaft out of the engine, ensuring the bearing inserts remain in place, and return the caps to their respective locations on the engine block, tightening the bolts finger-tight.

The engine should be positioned with the bottom facing up.

Clean the crankshaft with solvent and dry it with compressed air if available, ensuring to clean the oil holes with a stiff brush and flush them with solvent.