Honda BF20 BF2A Outboard Motors Manual, Page 19Get this manual
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5) Clean the cylinder head using wire brushCAUTION
Be careful not to damage the cylinder head gasket surfaceInspect cylinder head for warpage
5VALVE CLEARANCE
1) Remove the fan cover2) Remove the two mm cap nuts and the carburetor3) Remove the two 5x10 mrn flange bolts and the tappet cover
[I] TAPPET COVER
4) With the engine cold and the piston TDC on cornpression stroke, measure the valve clearanceStandard valve clearance INEX 0.08-0.16 rnm (0.003-0.006 in)