SonexBuilders.net

My aerovee has app 5 hours flighttime and the following problem : When rpm goes above 2500 right EGT rises rapidly and reaches max allowed at 2800 rpm ( 1400 F).
I have done the following : aligned the aerocarb so the slide is parallel to flight direction. Retorqued heads and adjusted valves.Adjusted secondary ignition. Intake elbows
removed and new coat of Permatex applied, hose clams tighten.
All this have had no effect, anything else I can do ??
Any reason why the intake elbow metal gasket is not used ??
Please help as I getting quite fed up with this problem

Kurt Nielsen
Baby lakes ( severely underpowered )

Sounds to me like you are going lean before full throttle.
Make sure your mixture arm is adjusted so that it's fully opened when the mixture control is all the way in. It might be there simply isn't enough fuel flow to run at WOT.

Then I would start adjusting the needle richer in small increments.

Remember, some times you just have to get the manuals out again and start from scratch to problem solve. One thing to check, as John can also attest to, is to make sure that the flat side of the carb needle faces the engine when mounted. You may also want to restart the adjustment at zero again with the mark on the needle as described in the book. But I know how you feel, I have had several induction leaks as well.

Thanks for the inputs ,I will try anything, even though the mixture control lever only has any effect in the middle 1/3 of travel .
Also the left side seems to be operating at correct temperatures i.e even temperatures up 2500 rpm then left indicates EGT 1100 F, CHT 300 F at 2800 RPM where right side starts to increase to EGT 1350 CHT 380.
GWMotley: I would be most interested to know where your leaks were
I`m going to try a richer mixture needle, just in case.
Kurt

Kurt, feel free to call
720-404-3158

You can verify your mixture arm is adjusted to give you enough fuel is to remove the tapered needle, set your mixture control to full rich, then let open your fuel valve. Catch the fuel as it drains through the aerocarb and measure the flow through the carb. It should be greater than 8-9 GPH. This is different than a flow test "to" the carb where you disconnect the fuel supply and measure. That should be greater than 20GPH.

As Gary mentioned, while tuning my carb, I mistakenly replaced the needle backwards, flat side facing filter. Ran fine at low RPM but really stuttered above mid throttle. Starting from scratch with the manual showed me the errors of my ways.