7CCM RPM Drop

[rogerj]

Just after takeoff, am consistently experiencing approx. 300 rpm drop during climb with C90 engine. Immediately level off and full power is restored after about 20 - 30 seconds. Can repeat at altitude shortly after initiating a climb. Also, no issue in level flight at full power (2475 rpm). Carb heat seems to make no difference. Ground run up with the tail tied is fine (~2200 rpm). Fuel flow from line at carb inlet is v. g. and screens are clean. Has 13 gallon fuel tank in each wing. The M-S carb has 470 hours since shop o.h. Mags check v.g. at all rpms.
Will appreciate sound advice. Thanks.
Roger J.

[Paul Agaliotis]

Sounds like a fuel level problem. Check the float height.
Paul

[rkittine]

Try putting on the Carb Heat immediately after lift off and don't wait for the RPM loss. - If the RPM rises, or is maintained (effectively enriches the mixture) than I agree and bet it is the float in the carburetor. Had the same problem on climb out on one of my Continentas. I would take off and it was not dependent on altitude, but pitch.

Bob