FlyFastJP
Well Known Member
My new-to-me RV-4 has the above engine. Not sure of which carb it has...I didn't take note of the part number when I had the cowling off. Winter upgrades are about to start tho.
Last flight, I noticed an rpm oscillation at about 1400. Goes up and down 50-75 rpm. No stumbling or stuttering...just steady up/down constantly. No fuel pressure gauge (guess builder didn't think one was needed...but I bought one), but it does it with and without boost pump. I don't recall it doing it on my first flight when I was checking stall, slow speed handling, etc.., but that doesn't mean it didn't. I may have just missed it.
Any ideas?
Last flight, I noticed an rpm oscillation at about 1400. Goes up and down 50-75 rpm. No stumbling or stuttering...just steady up/down constantly. No fuel pressure gauge (guess builder didn't think one was needed...but I bought one), but it does it with and without boost pump. I don't recall it doing it on my first flight when I was checking stall, slow speed handling, etc.., but that doesn't mean it didn't. I may have just missed it.
Any ideas?