Valve Spring Inspection

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.