2008 Yamaha WaveRunner FX SHO / FX Cruiser SHO Service Manual, Page 195Get this manual
Cylinder head
E 2Measure: Cylinder head warpage Out of specification Replace the cylinder headMeasurement steps: 1Eliminate carbon deposits from the combustion chambers2Check the cylinder head warpage using straightedge and thickness gauge in the directions shownCylinder head warpage limit: 0.1 mm (0.004 in)