Honda BF20A-BF25A, BF25D-BF30D Outboard Motors Shop Manual., Page 48Get this manual
5VALVE CLEARANCE COVER
Valve clearance inspection and adjustment must be performed with the engine cold
INSPECTION
1) Remove the engine coverRemove the flywheel cover or recoil starter
2) Disconnect the breather tube and oil return tube from the
cylinder head coverRemove the six 35 mrn flange bolts and cylinder head cover
3) Remove the sparks plugs and engine hanger bracketCAUTION To avoid water pump impeller damage, always turn the crankshaft in clockwise direction4) Manually turn the flywheel clockwise in the same direction as the arrow on the flywheelAlign the "T I" mark on the flywheel with theI" mark on top of the flywheel cover or recoil starter mounting bossThe" mark on the cam pulley will align with the "Tf" mark on the cylinder headIn this position the No1 piston is at top dead center of its compression stroke