Service Manual

6-8 CAMSHAFT/CRANKSHAFT

Breather

The function of the breather is to create a vacuum in the crankcase

which prevent oil from being forced out of the engine through the piston

rings, oil seals or gaskets. The breather has a reed valve (C), which limits

the direction of air flow caused by the piston moving up and down. Air

can flow out of the crankcase,but the one way reed valve blocks return

flow. It thus maintains a vacuum in the crankcase.

Oil laden air in the crankcase passes through the reed valve and

expand into the breather chamber. Here most oil separates from the air

and drains back to the crankcase. The air passes through a maze (E) and

vents to the air cleaner (F).

Removal

ORemove the breather chamber cover.

Unscrew the mounting screw (A), and remove the back plate (B) and

reed valve.

Installation Notes

Be sure the drain back hole (D) does not accumulate with slugges

before installing the breather valve.

@Align center of the valve seat with center of the reed valve and back

plate, then tighten the mounting screw.

NOTE

0 The mounting screw is a self-tapping one.

Be aware that

misthreading or overtightening screw will strip the female threads

and ruin the hole.

Inspection

inspect the reed valve for breakage, hair cracks or distortion, replace it

if necessary.

inspect the

back

plate for damage or rough contact surface, replace it

if necessary.

inspect the valve seating surface. The surface should be free of nicks

or burrs.