Question: priming possible but fuel in cut-off
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Hello Nick,
is possible to prime the engines while the fuel is in cut-off?Cheers
Michael -
No. The fuel pumps located near the fuel tanks will attempt to push fuel up to the point where the valve is shut (either mixture or firewall) and no further. There is no priming bypass to get around that. On most Fuel injected engines, the mixture levers connect to the FCU integrated into the engine-driven pump assembly located at the aft or rear of the engine. At this point there is a fuel return valve. This allows the pumps to help "clear the engine" mitigating vapor lock by flowing cooler liquid fuel through the system up to the aft of the engine. The fuel will never reach the fuel distributors or the cylinders with the mixture valve shut, but the system would theoretically be primed up to the mechanical pump. I do not believe Black Squares starting physics simulate the mechanical pump pushing the fuel to the distributors and into the engine while cranking which should allow for a good start with a warmer/ recently run engine.
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No. The fuel pumps located near the fuel tanks will attempt to push fuel up to the point where the valve is shut (either mixture or firewall) and no further. There is no priming bypass to get around that. On most Fuel injected engines, the mixture levers connect to the FCU integrated into the engine-driven pump assembly located at the aft or rear of the engine. At this point there is a fuel return valve. This allows the pumps to help "clear the engine" mitigating vapor lock by flowing cooler liquid fuel through the system up to the aft of the engine. The fuel will never reach the fuel distributors or the cylinders with the mixture valve shut, but the system would theoretically be primed up to the mechanical pump. I do not believe Black Squares starting physics simulate the mechanical pump pushing the fuel to the distributors and into the engine while cranking which should allow for a good start with a warmer/ recently run engine.
@SadBucket that's the process to clear vapour lock iirc.
Close throttle and mixture, run the pumps to cool down the lines.