JPKII

OK, so now that my electronics are getting sorted out on to the mechanicals...

I need help identifying the exact model of the OS engine and where I can find a manual or some type of parts breakdown.

It has the markings OS SX Max on one side with 91 on the other. The head is natural AL finish.

I've read about and seen pics of the SX-H but is there a difference between the -H and the regular SX?

The engine is brand new and has never been fired so I would need to know baseline carb settings, etc.

Thanks again for everyone's help.

BarracudaHockey

My Feedback: (11)

http://www.os-engines.com

The H is the helicopter version, large heatsink and probably a different carb.

misileman

My Feedback: (8)

If it has a 2 needle adjustment carb (click type for high end & 1/2 turn screw adjuster for low end), it's the OS91SX (original) before the C-spec type engine. The differance is internal parts, C-spec (pumped or not) have lighter crank, rod, & piston with more power and the 3 needle adjustment carb. There's not a bad thing about the old style SX engine, good power, easy to tune, parts still available. Heliproz still offers a blue hyper head for the old style SX along with replacement piston, rod, ect.
If you want more power from it, install a Perry pump on it. It's a very good engine, just not the hottest/latest thing on the market.