Because of the work challenge and given the fact that the work requires the use of specialized tools and equipment, it is recommended that the main work of cutting and grinding of the valves, the seats and the guides as they are widely referred to as the 'valve job', should best be done by a professional. It is easier for a home mechanic to pull the head, preliminary wash and examine the head and then take the head to a dealer service department or an automotive machine shop for the real service to be done on it. Performing the inspection enables identification of the state of the head and valve train parts and be aware of required work and new parts when interacting with an automotive machine shop. The dealer service department or the automotive machine shop will perform the valve and spring removal, valve and valve seat reconditioning or replacement, valve guide reconditioning, valve spring, spring retainer, rotator and keeper inspection and replacement when necessary, valve seal replacement, reconstruction of valves and valve components, and determination of the installed spring height. Also the surface of the cylinder head gasket will be ground if it is warped. After the valve job is done by a professional the head turn out to be like new with no or with negligible wear possible. After removal, it must be cleaned for the second time and, before being put in place on the engine, a thorough removal of any metal chips and other abrasive particles resulting from the valve work or the honing of the head must be accomplished with the aid of compressed air to clear all the oil ways and holes.