SCOTT42

My Feedback: (1)

Hello, I have an old OS 90 FS fourstroke engine that I need parts for but dont know where to get them at, I need mainly the oring set that goes with the pushrod sleeves, and a bearing thats 4mm X 21mm X 15mm for the cam, ive got everything else allready. Is the parts avliable?

Bax

My Feedback: (11)

Parts specific to the old O.S. FS-90 are no longer available from us or from O.S., in Japan. However, some parts are common to a lot of other engines. The o-rings for the pushrod tubes are universal. Here is the current stock number, which may work for you:

OSMG7372 24881824 O-RING IV/PRC #6H US$3.29 (4 per pack)

You'll have to do a search for the other parts. For the bearing, carefully measure the one you have and then check with one of the many bearing manufacturers for a replacement.

SCOTT42

My Feedback: (1)

Thank you Bax, How can I tell if I have the timeing set right when I put the engine back together? Thats another thing I worry about.

Bax

My Feedback: (11)

The large timing gear with the inner teeth has a dot on it. The small inner gear on the end of the crankshaft also has a dot. Then the engine is at Top Dead Center, the two dots line up.

SCOTT42

My Feedback: (1)

Thank you.