O.S. 70
 

I recently bought an O.S. 70 at a swap meet for $5 . It had been crashed but only tore off the rocker cover and part of the head casting where the rear rocker cover bolt threads into. Otherwise this engine is prestine, no other damage.
My question is,how do I tell the difference betwwen the 70 surpass and the 70 surpass II. I know it is not the new generation 70.
Please help[:o]

RE: O.S. 70
 

Hello; Doesn't the Surpass II have black rocker covers? I think the cast numbers are different as well. I don't have a "II" to look at but the 91 II has a nipple on the intake pipe for the engine vent, and I think the 70 has that nipple too.


It shouldn't be too tough to buy a new head and swap it all over. A friend gave me the remain of his FS 26 surpass. He idd an inverted pass down the local road and shaved the head down on it. The rocker cover is gone and the three mounting screws have been torn out leaving the screw holes ripped out. Oh yes, the crank was visibly bent as well. I have to decided to keep the engine for parts, as I have 3 others. I'm sure it would cost more to perair the engine then to buy a new one.

If you dedide not to repair the engine let me know, I'll buy it for parts, as long as the crank is straight.

RE: O.S. 70
 

Part of the problem I have is that I don't have the rocker cover or know anyone with a 70 currently to compare. The engine is worth keeping as everything else is straight. Getting the right parts is what I need to be sure of.
Thanks for the info.

RE: O.S. 70
 

Compare it to this picture of the OS70II Surpass. You'll notice the crank case vent is connected to the intake manifold

RE: O.S. 70
 

[sm=thumbup.gif]Thanks Havin Fun.
You have answered my question. This engine does not have that vent, and I already know that it is a Surpass from the casting on the side.
Thanks for everyones help.
Paul