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.