REMOVAL & INSTALLATION
See Figures 1, 2, 3, 4, 5, 6, 7, 8 and 9
Removal or installation of the valve springs requires use a valve spring compressor. There are several designs, like the leverage type, jawed type or C-clamp type. The C-clamp type is the most common for cylinder head service where the heads have been removed. All of the other types that are used with the cylinder heads installed require the use of compressed air to keep the valves from falling down inside the cylinder. A GM type Air Adapter tool No. J-23590 or equivalent can be used to retain the valves if the cylinder head using compressed air.
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.
See Figures 10, 11, 12 and 13
- 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. (1.6mm) or if the distortion exceeds 1 / 16 in. (1.6mm), 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/or compressed heights is checked, depending on the specification.