What is a Quick Way to Check Valve to Piston Clearance on an Assembled Engine?
Low tension checking springs, Part Number 99881-2, must be used (instead of your normal spring) to mock up your valve train and to check the piston to valve clearance on the engine. Assemble the valve train and verify correct lifter preload or valve lash. By mounting a dial indicator on the cylinder head with the plunger?s tip on the valve spring retainer, you can quickly check the clearance. Hand rotate the engine through a complete cycle (two rotations of the crankshaft), stopping at several points before and after Top Dead Center (T.D.C.) to check the valve clearance. The least amount of clearance will usually occur between 15 degrees before T.D.C. and 15 degrees after T.D.C. This also provides a graphic illustration that gross valve lift does not determine piston to valve clearance, as the piston is fairly far down in the cylinder when maximum valve lift is reached. By pushing the rocker arm down with your finger, the valve will contact the piston. The amount of movement shown on t
