TBI O-320 RPM Loss After Takeoff. RPM Dropped to around 1700-1800 RPM.
This is a new thread since I don't know that this is a fuel issue at this point.
I'm getting very frustrated with this intermittent problem and I am scared to fly the plane again until I solve it. I thought I had found the cause, fixed it, enjoyed a great performing engine on the test flight, flew and additional three hours, and then it occurred again.
What is making this so frustrating is that the problem is intermittent and I cannot find a pattern to safely reproduce it.
The next item I will be investigating is the possibility of sticking valves. I will probably have the engine shop do this work since I don't have all the specialty tools.
I'll be testing all the spark plugs again.
I also want to revisit the fuel tank vent. The vent line exits the top of the tank, turns down the firewall with a few zig zags, and exits the cowl at the bottom of the firewall. It terminates with a 45 degree forward facing cut. This is masked from direct airflow via the bottom lip of the cowl. Because of the zig zags, i have been unable to snake anything through it. I have hose clamped a rubber hose to it and can blow air through it. I can't gauge airflow through it. What else can I do here to check the vent line? (the last time this happened, the tank was 3/4 full and I had removed the cap from the tank to verify the fuel level. If the vent was blocked or partially blocked, would the problems start suddenly or gradually? I would think gradually.
I'll be getting a second set of eyes on the fuel system.
What else can explain this??
Thanks,
Glenn
This is a new thread since I don't know that this is a fuel issue at this point.
I'm getting very frustrated with this intermittent problem and I am scared to fly the plane again until I solve it. I thought I had found the cause, fixed it, enjoyed a great performing engine on the test flight, flew and additional three hours, and then it occurred again.
What is making this so frustrating is that the problem is intermittent and I cannot find a pattern to safely reproduce it.
The next item I will be investigating is the possibility of sticking valves. I will probably have the engine shop do this work since I don't have all the specialty tools.
I'll be testing all the spark plugs again.
I also want to revisit the fuel tank vent. The vent line exits the top of the tank, turns down the firewall with a few zig zags, and exits the cowl at the bottom of the firewall. It terminates with a 45 degree forward facing cut. This is masked from direct airflow via the bottom lip of the cowl. Because of the zig zags, i have been unable to snake anything through it. I have hose clamped a rubber hose to it and can blow air through it. I can't gauge airflow through it. What else can I do here to check the vent line? (the last time this happened, the tank was 3/4 full and I had removed the cap from the tank to verify the fuel level. If the vent was blocked or partially blocked, would the problems start suddenly or gradually? I would think gradually.
I'll be getting a second set of eyes on the fuel system.
What else can explain this??
Thanks,
Glenn
