Hammbone

When I bought my M20C it was doing the same thing. Like the others have said It was the pump o-ring. P.S. Never leave hydraulic flaps down on the ramp. The heat will cause the fluid to expand and blow the o-ring.

Please do not use a wooden dowel. The fuel will rapidly wick up the side of the dowel and give abnormally high reading. Sporty's sell one { plastic, 1" increments} and has a chart you fill out for your aircraft. These are accurate to within a gallon or less.

6" square piece of rubber baffle material. A flat weight of about 3 lbs. and 4 to 5" in diameter. It works in coastal North Carolina it will work anywhere. Don't let the $150 cost deter you.

You didn't say where you were located. I f you are in Denver there is nothing wrong with it

My guess is you are using original gauges. If so they can't be trusted any farther than you can kick an anvil. 300 deg. is getting low. You said the gauge was 200 which is pegged low. Very suspicious. Plus your oil temperature should be up to 180 after 15 to 20 min of flight at pretty much any power. Again gauge in accuracy.(Unless your therm. valve is stuck open)

Ahoy DXB. Several items can effect total fuel flow other than the carb. is the throttle against the open stop? Is the mixture against the open stop? Assuming a Vernier control, after it is pushed in. continue to turn clockwise until it stops. are you sure your prop is turning 2700 rpms. Tachs are notoriously inaccurate. A governor adjustment would fix this. These are cheap fixes compared to pulling a carburetor. Finally if you climb at Vy { 100 mph) for more than a minute or two, the back cylinders will overheat. Try 110 to 120 instead. I think you will find your CHT's will run lower and climb rate will suffer only a modest decrease. Hope this helps.