PLUG-PIPE 7W6492 - Caterpillar

Perform this test in order to determine if a valve guide should be replaced.
Illustration 1 g00314806
Measure the radial movement of the valve in the valve guide.
(1) Valve guide
(2) Radial movement of the valve in the valve guide
(3) Valve stem
(4) Dial indicator
(5) Valve head
Place a new valve in the valve guide.
Place a dial indicator with a magnetic base on the face of the cylinder head.
Lift the edge of the valve head to a distance of 15.0 mm (0.60 inch).
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.
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. The maximum clearance for the inlet valve stem in the valve guide with a valve lift of 15.0 mm (0.60 inch) is the following value. ... 0.08 mm (0.0031 inch)The maximum clearance for the exhaust valve stem in the valve guide with a valve lift of 15.0 mm (0.60 inch) is the following value. ... 0.09 mm (0.0035 inch)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.