Cross posted from the L-4 & NE-1 forum:
For over a year now I've had a continuing problem with my L-4A: the engine dies shortly after landing. This continues.
"Acts just like vapor lock in the fuel lines."
I believe that's exactly what the problem is, and that there may be a basic feature of the design or installation that's being violated. Contributor Reileyr wrote, "For a 'normal' installation, there is no place for air to get trapped. Richard". This is what's happening. There's a large air or gas bubble visible in the top of the glass walled gascolator each time the engine dies. It's building up there and blocking fuel flow, instead of just bubbling harmlessly back up into the fuel tank, as it should.
After purging the fuel system I might get one or two flights out of it, but the problem invariably surfaces again.
All connections are tight. There's no fuel smell or evidence of leakage. Only 100LL is used, and there are no tell-tale blue dye streaks anywhere.
Could the gascolator have been mounted in the wrong place during the most recent restoration? Is there a high point in the fuel system where air or gas bubbles can collect?
I'm asking anyone who might have one for a blueprint or schematic of an L-4A (or B, H or J) firewall, so that we can determine the original factory correct gascolator location.
Everything else even remotely related to the fuel system has been checked, inspected, replaced, or overhauled. Everything. There are no induction leaks. Engine compressions are excellent. The fuel lines are new. Fuel flows like crazy. Mags have been inspected, and the carb overhauled. There's nothing that hasn't been looked at by throughly knowledgeable people.
Thanks much!
Howard
For over a year now I've had a continuing problem with my L-4A: the engine dies shortly after landing. This continues.
"Acts just like vapor lock in the fuel lines."
I believe that's exactly what the problem is, and that there may be a basic feature of the design or installation that's being violated. Contributor Reileyr wrote, "For a 'normal' installation, there is no place for air to get trapped. Richard". This is what's happening. There's a large air or gas bubble visible in the top of the glass walled gascolator each time the engine dies. It's building up there and blocking fuel flow, instead of just bubbling harmlessly back up into the fuel tank, as it should.
After purging the fuel system I might get one or two flights out of it, but the problem invariably surfaces again.
All connections are tight. There's no fuel smell or evidence of leakage. Only 100LL is used, and there are no tell-tale blue dye streaks anywhere.
Could the gascolator have been mounted in the wrong place during the most recent restoration? Is there a high point in the fuel system where air or gas bubbles can collect?
I'm asking anyone who might have one for a blueprint or schematic of an L-4A (or B, H or J) firewall, so that we can determine the original factory correct gascolator location.
Everything else even remotely related to the fuel system has been checked, inspected, replaced, or overhauled. Everything. There are no induction leaks. Engine compressions are excellent. The fuel lines are new. Fuel flows like crazy. Mags have been inspected, and the carb overhauled. There's nothing that hasn't been looked at by throughly knowledgeable people.
Thanks much!
Howard
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