I fly a 1973 7GCBC with a 150 HP Lycoming. For a one hour flight at 2300 RPM my fuel consumption is 10.8 US gallons! I don't see leaks. I changed my fuel caps. Is it a carburator problem? Thanks.
I probably found the reason, or one of the reasons, why my engine was burning too much fuel. I checked my RPM with an electronic device and when I was cruising at 2200 RPM I was in fact at 2350! I didn't have the time to check my consumption but my cylinder temperature are more even now. The 2 at the back being a little bit warmer.