Valve guide clearance is the clearance between the valve stem and the tube or guide into which the valve is inserted. Valve guide clearance is an important aspect of engine rebuilding — with too much clearance oil can seep down the stem into the cylinder. If this happens the oil will burn in the cylinder and cause the engine to use excessive oil and smoke. Too little valve clearance and the valve will not get enough oil to dissipate the heat and may seize up in the valve guide.
Things You’ll Need
Safety glasses, Work bench, Dial bore gauge, Micrometer, Shop wipes