Valve guides are cylindrical pieces of metal pressed into the cylinder head on your engine. Valve guides are used to positively locate the valves in the cylinder head so that they make proper contact with the valve seats.
The clearance between the inner diameter of the valve guide and the outer diameter of the valve stem is critical, as with too little clearance, the valves can stick and with too much clearance, the valves may not seat properly, leading to lost power and increased oil consumption.
Over time, the inner diameter of the valve guide can wear, and once this happens the valve guides should be replaced in order to keep your engine running at its best.
This Part Fits the Following Vehicles
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