Mazda MX-5 Miata Sport 2007 Manual page 36

2007 Mazda MX-5 Miata Sport
2006-08 ENGINE Mechanical - Overhaul - 2.0L (LF) & 2.3L (L3) - Mazda6 & MX-5 Miata
Fig. 36: Performing Valve Spring Inspection
Courtesy of MAZDA MOTORS CORP.
2. Measure the out-of-square of the valve spring, using a square, as shown in the figure.
1. Rotate the valve spring one full turn and measure "A" at the point where the gap is the largest.
If it exceeds the specification, replace the valve spring.
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Valve spring out-of-square (Maximum)
1.95 mm {0.0767 in}