Anyone have a copy of an OS FS-90 instruction manual that they are willing to share? Lost mine somehow, or maybe I just forgot about that special place I where I left it(senior CRS syndrome). Anyhow, I'll remember the doner in my will (LOL).
Phil AMA609
How much info do you require? the usual requests relate to the timing =
On the ring gear that's installed in the rear housing of the O.S. Max FS-90 engine, you'll see the ends of three screws and one small dot. When the piston is at Top Dead Center, the dot is centered at the top. When you install the rear housing, remove the small cover at the back...it's held in with a rubber o-ring. You can use your finger on the head of the screw that's there to keep the cam assembly from rotating while you install the housing onto the engine. Please note that if you must take the cam assembly apart, the screw at the rear has a REVERSE thread, and you must turn it clockwise to loosen it, otherewise you may break it off, and then your engine will be toast, since parts are not available to make that repair.
Alternate Bearing Numbers from a local supplier = Front: R6AZ, Rear: 6001, Crankshaft = Front MR2015 [15 X 20], Middle 607, Rear R4,
Please email direct for jpegs of exploded view etc. see also Alan's Hobby, Model & RC Web Links
regards Alan T. Alan's Hobby, Model & RC Web Links
I have one that belongs to an engine with a busted case. Email me your address and I will drop it in the mail to you.
John VB
Try the OS Web Site -- They have most manuals on line.
Cheers -- \_________Lyman Slack________/ \_______Flying Gators R/C___/ \_____AMA 6430 LM____ / \___Gainesville FL_____/ Visit my Web Site at
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