Valve Guide: Testing and Inspection

TOOL REQUIRED
- J 26900-1 Outside Micrometer
- J 26900-14 Small Hole Gages

MEASURE





1. Valve stem outside diameter using a Outside Micrometer and record the measurement. The standard outside diameters for valve stems are 5.457 to 5.480 mm (0.2148 to 0.2157 inch) for intake valves and 5.440 to 5.455 mm (0.2142 to 0.2148 inch) for exhaust valves. Measure the diameter at more than one place along the length of the valve stem. Record measurement.





2. Valve guide inside diameter using a Small Hole Gages with the Outside Micrometer.Insert the appropriate size Small Hole Gages into the valve guide and measure the inside diameter. Remove the Small Hole Gages and, using the Outside Micrometer, read the diameter of the Small Hole Gages and record the measurement. The standard inside diameter of valve guides is 5.500 to 5.512 mm (0.2165 to 0.2170 inch) for both intake and exhaust valve guides. Measure the diameter at more than one place along the length of the valve guide. Record measurement.
3. Valve stem-to-valve guide clearance by subtracting the valve stem outside diameter measurement from the valve guide inside diameter measurement. Standard clearances are 0.020 to 0.055 mm (0.0008 to 0.0022 inch) for the intake valves and 0.045 to 0.072 mm (0.0018 to 0.0028 inch) for the exhaust valves. If the intake valve guide clearance exceeds 0.070 mm (0.0027 inch), replace the intake valve and valve guide. If the exhaust valve guide clearance exceeds 0.090 mm (0.0035 inch), replace the exhaust valve and valve guide.