Valve Spring Testing
The valve springs should be tested whenever removed for inspection, reconditioning, or replacement. Valves have 2 springs, and inner and an outer. Before testing, the 2 springs should be separated.
CAUTION:
Identify valve springs because they are to be used in matched pairs only. When replacement is necessary, replace springs as a pair. Do not replace only inner or outer springs.
- Obtain specifications for spring tension at specified spring length. See ENGINE SPECIFICATIONS . Turn table of special tool (C-647) until surface is in line with spring length specification mark on threaded stud and zero mark is on front.
- Place inner spring over stud on table and lift compressing lever to set tone device. Pull on torque wrench (beam or dial type) until ping is heard. Take reading on torque wrench at this instant. Multiply this reading by 2. This will give the spring load at test length.
- Compare reading to specification. Discard springs that do not meet specifications. Readjust table to specified length for testing outer spring. Repeat previous steps.