Valve Spring Inspection

WARNING: This page is about a different car, the 2005 Mazda MX-5 Miata, 2004 Mazda MX-5 Miata, and 2003 Mazda MX-5 Miata. However, it is still accessible from the selected car via links, so may be relevant.

Apply pressing force to the pressure spring and measure the spring height. Replace the valve spring as necessary.
Pressing Force
1. IN: 172.60-195.15 N
2. {17.6-19.9 kgf, 38.72-43.78 lbf}
3. EX: 172.60-195.15 N
4. {17.6-19.9 kgf, 38.72-43.78 lbf}
Standard Height
1. IN: 39.5 mm {1.56 in}
2. EX: 39.5 mm {1.56 in}
  
  Fig 1: Measuring Spring Height Under Pressing Force
  Courtesy of MAZDA MOTORS CORP.
Measure the out-of-square of the valve spring. Replace the valve spring as necessary.

Fig 2: Measuring Valve Spring Out-Of-Square
Courtesy of MAZDA MOTORS CORP.

VALVE SPRING OUT-OF-SQUARE SPECIFICATIONS

Valve Spring	BP - mm {in}	BP with TC - mm {in}
IN	1.63 {0.064} max.	1.58 {0.062} max.
EX	1.63 {0.064} max.