Agreed, it's over heating in hover, However.....

This being a OS32, no one mentioned that it is the low speed needle that needs adjusting for hover. The High speed needle should be adjusted for a good climbout, and the LS adjusted for a nice, rich hover.

On the OS32, depending on fuel used, the HS will wind up being somewhere between 1 and 1 1/4 turn open. On the low speed, I adjust it initially to be very rich at idle, as in I let it idle, then pinch the fuel line shut. I want to get about 4-5 seconds of time BEFORE the engine RPM increases from going lean because of the pinched off line. Then I fly it in hover, and will usually have to richen it, (the LS needle), to get the engine temperature happy for hovering.

Now that chirping sound. . Man that could be anything. Not knowing much about your heli, I probably won't be any use here. But, On the shuttle, the starter shaft going into the clutch is a very likely canidate for chirping, what I don't know is wether or not your bird's starter system is simular or not.

Hope this helps!

CeeJay