It is recommended that in case of any signs of corrosion and worn out they should naked viewed to determine the extent of service that the valve need in the course of overhauling of an engine. Remove every vestige of the old gasket material and sealant off the head gasket, intake manifold, and exhaust manifold surfaces without cutting the cylinder head. Disconnect from the radiator and scrub out all the accumulated scale from the coolant passages and pass a wire brush through various holes to remove deposits. Insert a tap of suitable size into each tapped hole to wash out the corrosion and the thread sealant, and blowing the hole with compressed air after mounting eye protection. Thoroughly scrub the exhaust manifold and intake manifold stud threads with the wire brush, and then use solvent to clean the cylinder head; blow dry the cylinder head with compressed air to hasten the drying process. Cleaning and decarbonizing chemicals may be of help in cleaning up cylinder heads and valve train parts but their use should be done so carefully. All valve springs, keepers, and retainers must be cleaned to the extent that no dirt present can take a blue loctite color if applied thereon; the cleaning must be done in such a way that; no two like-distinct part should be accompanied so that they cannot mix, and make sure that all steam seal are dry. Remove large deposits from the valves and clean the valve heads and stems using a motorized wire brush; make sure that valves are neat. Check the head for cracks, leakages and any other signs of damage consult the automotive machine shop if needs be. Unsigned head gasket mating surface should be checked with straightedge and a feeler gauge and if the warpage is greater than the permissible limit, it can be machined. Check the valve seats for pitting, cracking or burning and check the valve stem to guide clearance with the help of a dial gauge. Over the face of each valve, carefully check for signs of wear, deformation, and cracks and, measure the diameter of the stem at least three points. For each valve spring; inspect, look around for wear and pits, check and compare its free length and replace any that are short. Go round each spring every spring and ensure that it is square by placing a level board on top of it; the distorted or the sagged springs should be replaced. Check the amount of wear and cracks on the spring retainers, spring seats, and keepers and replace if they seem weak. Last of all is the examination of the camshaft bearing journals on the cylinder head to have checking of the valves since whether or not a cylinder head can be saved is determined by the condition of the camshaft bearing journals; if these are gouged or scored, the cylinder head will have to be replaced in any case, no matter the state of the valves and other related parts that may be sent to a machine shop for servicing. If the visual inspection shows that the components of the valve are poor and worn out beyond the stated limit, then re-installing them in the cylinder head is necessary.