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FS 70 Surpass Gaskets?

Old 12-09-2020, 05:42 PM
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Default FS 70 Surpass Gaskets?

I just rcvd an FS 70 Surpass (II?) from Ebay; Seller states it came from an estate and has no personal knowledge of the engines history. I have several questions:
1) Is this engine a surpass or Surpass II? It has the Black valve cover, and the carb is centered in the rear, but the side of the crankcase just says Surpass.
2) When I removed the intake pipe to rotate the Carb 180 degrees to line up the existing throttle linkage, there was NO gasket between the intake pipe and the head.
Should there be? I can't imagine an ICE without an intake gasket of some sort. The manual I found on line was a PDF, not very clear, and I couldn't see a gasket listed or shown there.???
3) Since the Intake pipe was off, I pulled the back cover, and again, NO gasket. The inside of the crankcase was relatively clean, bearings were smooth, so I put it back together loosely. Haven't tried to run it yet.
4) How much compression should this engine have when turning by hand? Didn't feel like much at all, and when turning it in the proper direction, there was some air being blown back out of the carb.
From my 40 plus years in the auto repair business, this would indicate a valve timing issue. The valves operate smoothly, & from what I can see through the intake and exhaust ports, the valves are not/were not interfering with the piston.
I read up on line regarding the cam timing and valve adjustment, but haven't pulled those covers yet, wanted to find out about the gaskets first.
My automotive compression gauge is MUCH to big to fit in the glowplug hole, but I suppose I could rig something up with plumbing fittings and adapt it to fit.
Thanks in advance for any and all advice.
Old 12-27-2020, 08:45 AM
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I am looking at the OS FS70 II parts diagram and I do not see any gaskets between on the intake as well as the back. I see them shown for the FS91. I have attached the manual that I have. Hopefully the upload feature has worked.

There should be compression as you turn the prop. Regarding timing you can do a search and find videos/articles. This link should help.

Finally once you've checked the engine and made sure that timing is OK, try to run it. The manual that I have attached provides you with what to use for a prop and if you were to do a search, you may be able to find what to expect for the engine RPM using that prop.

Attached Files
File Type: pdf
fs-70s-ii-91s-ii-p-manual.pdf (1.34 MB, 36 views)

Last edited by ahdofu; 12-27-2020 at 09:51 AM.

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