Valve Guide Reaming
WARNING: This page is about a different variant/trim than selected.
- Using a dial indicator, measure the valve stem-to-guide clearance. Position the tip of the dial indicator at the top of the valve guide.
Valve stem-to-guide clearance may also be obtained by using a micrometer to measure the valve stem diameter and a ball type measuring gage to measure the guide bore.
- A valve stem (1) and guide (2), with excessive clearance, must be replaced or the cylinder head replaced. Refer to Engine Mechanical Specifications .
- Inspect the valve stems for excessive scoring, wear, or warpage.
- A valve stem that has excessive scoring (3 or 4) or wear (4 or 6) must be replaced.
- If a valve guide is worn or has excessive stem-to-guide clearance, the cylinder head should be replaced.
- Measure the valve stem diameter. A valve stem with a diameter less than 7.95 mm (0.313 in) must be replaced.
If the valve stem diameter is within specifications, and the stem-to-guide clearance is excessive, the cylinder head must be replaced.
CAUTION:
Excessive valve stem-to-guide clearance may cause a noisy valve train, premature valve stem oil seal wear, component damage, and/or excessive engine oil consumption.
CAUTION:
Insufficient valve stem-to-guide clearance will result in noisy or sticking valves. Valves that are too tight may disturb engine smoothness or lead to component damage.