The valve springs are removed and installed as part of the valve procedure found earlier in this section. If only a spring replacement is required, refer to the valve stem seal procedure with the cylinder head installed. The same air pressure method may be used to retain the valve while only a spring is replaced.HEIGHT AND PRESSURE CHECK
- Place the valve spring on a flat, clean surface next to a square.
- Measure the height of the spring, and rotate it against the edge of the square to measure distortion (out-of-roundness). If spring height varies between springs by more than 1 / 16 in. or if the distortion exceeds 1 / 16 in., replace the spring.
A valve spring tester is needed to test spring test pressure, so the valve springs must usually be taken to a professional machine shop for this test. Spring pressure at the installed and compressed heights is checked, and a tolerance of plus or minus 5 lbs. (plus or minus 1 lb. on the 231 V6) is permissible on the springs covered in this guide.VALVE ADJUSTMENT
In the event of cylinder head removal or any operation that requires disturbing or removing the rocker arms, the rocker arms must be adjusted. See the Valve Lash procedure found earlier in this section.