Perkins — Perkins Industrial Engine Manual (EN)

Air Inlet and Exhaust System 72 UENR0623-02 3. Lift the edge of the valve head to a distance of 15 mm (0.591 inch). 4. Move the valve in a radial direction away from the dial indicator. Make sure that the valve moves away from the dial indicator as far as possible. Position the contact point of the dial indicator on the edge of the valve head. Set the position of the needle of the dial indicator to zero. 5. Move the valve in a radial direction toward the dial indicator as far as possible. Note the distance of movement which is indicated on the dial indicator. If the distance is greater than the maximum clearance of the valve in the valve guide, replace the valve guide.

Refer to Specifications, “Cylinder Head Valves” for the clearances. The original valve guides are bored into the cylinder head. When new valve guides (1) are installed, new valves and new valve seat inserts must be installed. The cylinder head must be rebored in order to install the new valve guide. For more information, contact your distributor or your dealer.