The crankshaft should be refitted with new main bearing cap bolts every time. The crankshaft can be removed easily only when the engine has been pulled out from the vehicle. If the crankshaft to be removed measure the end play using a dial indicator or feeler gauges as explained above. Remove the main-bearing cap bolts, and with a soft-faced hammer, knock on the caps to free them from the block. Finally and with the help of another person, raise slowly but carefully the crankshaft out of the engine block. Before mounting you should always clean the engine block and the crankshaft and check for defects. Scrape the bearing surfaces and oil holes, and place two sets of new upper and lower main bearing inserts. Place the crankshaft back into the cylinder block, and screw the main bearing caps in the correct manner with the bolts tightened. This is done by inserting plastigage between the main bearing caps and comparing the gap with the standard one. If necessary replace the bearing inserts with the correct size. Remove any of the plastigage material and polish the bearing surfaces. Transfer the engine oil on the bearings and fit the main bearing caps and fasten them to the appropriate recommended torque and rotating angle. Check crankshaft end float again and then attempt to turn the crankshaft with your hand to find out if it binds. Timken now has a supply of the part number 3345 new rear main oil seal which should be installed.