Had the same problem and has anyone thought to check the fuel tank? My ASP .61 FS runs GREAT on my break in stand with needle valve exactly at the half way height of the tank. But when I put it in the plane where the top of the tank is just below the needle it won't idle worth a darn. I put a fuel pump on it and it ran perfect! It might be the tank is the problem. Placement, leaks, kinks, clog, etc.....
Originally Posted by
w8ye
The OS 52 carb is a direct bolt on swap.
I've also seen Magnum carbs on the OS engines.