How to Use a Valve Spring Micrometer
- 1). Disassemble the assembly and remove the valve spring, then reassemble the assembly with the micrometer inserted in place of the valve spring. Include any shims that are known to be necessary based on your model (consult your car's manual to find out which are necessary).
- 2). Rotate the thimble on the micrometer to open the micrometer. The micrometer pushes the retainer up into the valve lock. Continue until all slack is removed from the micrometer thimble.
- 3). Read the measurement on the valve spring micrometer. Compare the reading against the valve spring installed height required by the camshaft's specification card. The difference is the distance you must shim, or remove, from the valve spring.
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