2007 Johnson 2 HP 4-Stroke Service Manual, Page 80Get this manual
POWERHEAD CYLINDER HEAD
Cleaning and Inspection
IMPORTANT: If any excessive wear, cracks,
defects, or other damage is found on any component, replace
Cylinder Head Distortion
Using straightedge and thickness gauge, measure the gasket surface of the cylinder head at six locations as shownCylinder head distortion: Service limit: 0.002 in(0.05 mm)
Cylinder Head
Remove all carbon from the combustion chamber
IMPORTANT: Do not use any sharp edged tool
to scrape carbon off the cylinder head or componentsDO NOT scuff or nick the metal surfaces when decarboning