If you want to reuse your crank, it's always a good idea to have it magnafluxed to check for cracks. Even if nothing is done to the crank, the piece must be thoroughly cleaned before reassembly. This includes the oiling holes, which can be done with a small, circular brush. Cleaning doesn't have to be done in a solvent tank such as this. You can do it in your driveway with a water hose and a bucket of soapy water. Just make sure to apply a coat of rust inhibitor such as WD40 after you are done.