Dealerships and auto parts stores often have new or remanufactured cylinder heads for most engines. Some specialized tools are necessary for the disassembly and Inspection procedures, and replacement parts may be scarce leading to it being more practical for a home mechanic to buy replacement heads instead of disassembling, inspecting and reconditioning the original ones. Intake and
Exhaust Valves as well as related components should be taken off during cylinder head disassembly. If they're still in place, remove the rocker arms (3.3L only) and the lifters and camshafts from the cylinder head. Parts should be labeled or stored separately so that they can be properly reinstalled in their initial areas. Don't put down 3.3L engines on their sides or upside down, while laying down lifters because the lifter would airlock thus requiring bleeding. The lifters can only be placed on their side provided they are submerged in a pan of clean engine oil until reassembly takes place. Before removing valves ensure that all their related components along with them are labelled so that they can remain separate and reinstall them into the valve guides where they were removed from. Use a spring compressor to compress the springs on the first valve after which remove valve stem keepers from it. Be careful when releasing the valve spring compressor so as to avoid damaging anything else like retaining clips, springs, seats etcetera (if used). Take out one of valves from its engine head then get rid of oil seal from guide as well. If a valve binds in its guide (won't pull through), push it back into the engine head then deburr around this valve's stem keeper groove using fine file or whetstone tool. Repeat this process with other valves too. Ensure you keep all parts pertaining to each particular valve together such that when reinstalling happens, each will return to its original location. Once all valves are taken out, and their related components kept in an organized way, the whole head must be washed and examined. If you are performing a complete engine overhaul, finish the engine teardown before starting the cylinder head cleaning and inspecting process.