Whenever machine work is performed on a crankshaft’s journals, these surfaces must be adequately finished before use in an engine. Besides maintaining a sufficient microfinish, it is also important that any burrs are removed. A critical area where burrs are often found are just inside of the journal’s oil passages. The way to remove these burrs is by using a process known as chamfering.
Burrs develop on oil passages from a variety of machining operations. Just grinding the crankshaft .010” can leave a small burr that would restrict the proper flow of oil while the engine is running. This poses a serious concern since engine bearings need to be adequately lubricated at all times. Chamfering is the industry standard in deburring crankshaft oil passages, which is explained in more detail below. Continue reading