Vapor Lock In Port Injection Application
Vapor Lock In Port Injection Application
(OP)
Hello,
I am working on an industrial application with a port injected gasoline engine and am having vapor lock issues due to the temperature of the bulk fuel and inlet vacuum. Due to design constraints I am not able to flood the inlet of the fuel pump or use an in-tank pump. I am also stuck with a bulk fuel temp of 135° F, due to design constraints. Does anyone have any ideas how I can keep the fuel from vaporizing in the inlet fuel line? Is there a such thing as a pre-charge or lift pump for unleaded gasoline?
Any help would be appreciated.
Thanks J
I am working on an industrial application with a port injected gasoline engine and am having vapor lock issues due to the temperature of the bulk fuel and inlet vacuum. Due to design constraints I am not able to flood the inlet of the fuel pump or use an in-tank pump. I am also stuck with a bulk fuel temp of 135° F, due to design constraints. Does anyone have any ideas how I can keep the fuel from vaporizing in the inlet fuel line? Is there a such thing as a pre-charge or lift pump for unleaded gasoline?
Any help would be appreciated.
Thanks J





RE: Vapor Lock In Port Injection Application
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pat pprimmer@acay.com.au
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RE: Vapor Lock In Port Injection Application
RE: Vapor Lock In Port Injection Application
Most electric FI pumps intended for frame/chassis installations need either a gravity feed or an in-tank lift pump. Some mechanisms don't respond well at all to any depression in the connection between the bulk fuel storage and the pump inlet - gasses evolve easily with reduced pressure and the pump will lose prime and generate noise. The roller cell types (e.g. Bosch) are the worst.
I would be inclined to try pressurising the tank, just slightly, and using a gear-type ('gerotor') pump in a frame/chassis-mount package as, in my experience, the gerotors can generate a reasonable 'lift' and if, as suggested earlier, you can contrive to keep the bulk fuel temperature down, a reliable fuel supply can be established.
Walbro is the pump I have in mind.
Try http://www.gnttype.org/techarea/fuelsystem/walbrof...
for some flow data and some pump dimensions.