Cylinder Head Bolts Outer Diameter

Cylinder head bolts are tightened by plastic zone tightening method. Whenever the size difference between (d1) and (d2) exceeds the limit, replace them with a new one.

Fig 1: Identifying Cylinder Head Bolts Measuring Point
Courtesy of SUZUKI OF AMERICA CORP.

Limit [(d1) (d2)]: 0.23 mm (0.0091 in)
If reduction of outer diameter appears in a position other than (d2), use it as (d2) point.