Vapor Lock™ has been approved by independent lab testing as an ASTM C 494 Type S concrete admixture no other competitor in this segment has this important industry approval.
Here is an outline of some of the benefits of Vapor Lock™ Concrete Admixtures
That's about 10.5 psig.Vapor Lock ™ is manufactured with great pride by The Specialty Products Group, Inc.
I'm partially with Roger it's unlikely that vapor lock occurred, but it's still quite possible. Doing the former requires a differential fuel flow indication system if fuel flow readings are desired).Īll that said, the answer to the engine quitting is correct: turn on the boost pumps. Even in the 912 carb engines Rotax strongly recommends a restricted return line after the fuel pump to the fuel tank, or will accept a return line to the gascolator (Flight Design does the latter. It's vitally important to avoid having high points in a system unless you supplement it with pumps, return lines, or some kind of air bleed. In order to purge that air, you basically have to either raise the fuel pressure to push it past, or open the fuel line so that the flow rate is faster than the air bubble's ability to stay in the U bend. Enough air will actually act like a constriction on the line, fuel tries to push past it but you're only going to get a little bit of a trickle. If air forms, it will float to the high point in that bend and get trapped. But, what if we put a U bend in it somewhere in the belly so that there's a high point? This U bend becomes the vulnerable point to vapor lock. In this configuration, if air forms anywhere in the system, it will either float up to the wings or up to the fuel pump and get purged by head pressure. Fuel goes from the wings, down into the belly before going back up to the engine fuel pump. Imagine an aircraft that has high wings and tractor configuration. That's why low wings have boost pumps in the wings or belly, and often high wings do not. Note that I said USUALLY. Even if vaporization occurs, the high wing head pressure will USUALLY push the air out low wings do not get this luxury. Low wing aircraft suffer this same problem, while high wings usually don't. It doesn't matter what kind of engine it was, the problem is the fuel was not being drawn from the tank and starving the engine. and many pumps that work with gasoline don't work with air. The problem with the gases (the phase, not gasoline) is it takes up DRAMATICALLY more space than liquids do, raising pressure as the phase change occurs, and it's really, really difficult to draw fuel past it. What would happen is the fuel would be drawn up to the engine and sometimes lower the pressure enough that vaporization occurs. In those days, there weren't fuel pumps in the gas tanks. At the time, there was no fuel pump in the gas tank. Vapor lock is something that started back in the days of old automobile engines.