Saito fg60r3 radial overheating
 

I think my saito 60cc radial is overheating. Ive run several tanks thru it on the plane without the cowel just fine. Installed the cowel and it slows and stops. Cyl temps look to be around 175 deg but no.1 a bit higher. Any thoughts?

Yes, especially if this is a new engine............................................ ........... The nitro content of the fuel is too high.............................................. .... the engine is running too lean.