Valve Guide Measurement
WARNING: This page is about a different car, the 2017 Chevrolet Spark. However, it is still accessible from the selected car via links, so may be relevant.
- Measure the valve stem (1)-to-guide (2) clearance. Excessive valve stem-to-guide clearance may cause an excessive oil consumption and may also cause a valve to break. Insufficient valve stem-to-guide clearance will result in noisy or sticking valves.
- Clamp the GE-7872 indicator to the cylinder head at the camshaft cover rail.
- Locate the dial indicator so that the movement of the valve stem from side to side, crossways to the cylinder head, will cause a direct movement of the indicator stem. The dial indicator stem must contact the side of the valve stem just above the valve guide.
- Drop the valve head about 0.064 mm (0.0025 in) off the valve seat.
- Use light pressure when moving the valve stem from side to side in order to obtain a clearance reading. Refer to Engine Mechanical Specifications (L5Q)Engine Mechanical Specifications (LV7) for proper clearance.
- If the clearance for the valve is greater than specifications and a new standard diameter valve stem will not bring the clearance within specifications, replace the cylinder head.
NOTE:
Valve guide wear at the bottom 10 mm (0.390 in) of the valve guide is not significant to normal operation.