This should be done professionally due to the nature of the job and the underlying tools and equipment that are needed to carry out the service, which include; the valve job which involves service of the valves, the valve seats, and the valve guides. A home mechanic can take off the heads and partially disassemble them; allowing preliminary cleaning and inspection to be performed ; then reassemble them and take them to an automotive machine shop for the work to actually be done on them. Carrying out the inspection enables the evaluation of the general status of the
Cylinder Head and valve train parts so as to determine the required work and new parts required when dealing with an automotive machine shop. Under the category of the machine shop, it will include the services such as removal and replacement of valves and springs reconditioning or replacement of the valves and the valve seats as appropriate, checking or replacement of the valves guides, checking or replacement of the valve spring, spring retainer and the valve stem locks depending on their state among other services such as replacement of the valve seals, reassembly of the valves and ensuring that the installed spring height is correct Also, if les worn or warped the cylinder head gasket surface will be resurfaced. Afterwards, the valve job that is done expertly sees the cylinder head of a vehicle coming out as brand new. There should be a thorough cleaning of the cylinder head when it comes back after the valve job or when after the cylinder head was machined and all the deposits, metal chips and other abrasive grits must be removed before its installation on the engine by blowing compressed air through the oil holes and passages, if any.