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Workshop => Carburetor, Intake, and Exhaust => Topic started by: JesseA420 on April 24, 2015, 11:38:24 AM

Title: hooking up vacuum fuel pump
Post by: JesseA420 on April 24, 2015, 11:38:24 AM
all these higher flow fuel pumps i can find seem to be dual outlet. how do you hook these up on single cylinders? just plug one of the outlets? run both outlets to a Y in the fuel line then a single line to the carb?
Title: hooking up vacuum fuel pump
Post by: Quick310r on April 24, 2015, 12:44:53 PM
I just plug one off.
Title: hooking up vacuum fuel pump
Post by: Rupp250 on April 24, 2015, 01:19:52 PM
I just run one that is single outlet......or you can plug an out let. can get the silicone plugs for vacuum line at any vatozone.
Title: hooking up vacuum fuel pump
Post by: JesseA420 on April 24, 2015, 01:28:38 PM
you got a link to a high flow single outlet? the only ones i see that are high flow are at least dual outlet.
Title: hooking up vacuum fuel pump
Post by: mx250r91 on April 24, 2015, 01:41:43 PM
Here's the mikuni pump the old single carb sleds use:
(http://www.mikuni.com/fuel_pumps/fuel-pump-df44-211.jpg)

http://www.mikuni.com/c-fuel_pumps.html
Title: hooking up vacuum fuel pump
Post by: Jerry Hall on April 24, 2015, 07:21:37 PM
You will need to use a float valve size in the 1.5 to 2.5 range depending on the maximum pressure your system will make........ Always use a float valve size that is as large as possible and will still control the fuel level without running the float bowl over.
Title: hooking up vacuum fuel pump
Post by: udontknowme on April 24, 2015, 09:14:05 PM
far as i know the highest volume pump is the black mikuni. they work great and looked to be the highest qaulity pump i could find. i guess you could plug one outlet or use a Y and a single line from there to the carb which is what i did and it works good. i have no idea how well the smaller silver pumps work. if you do use a 2 into 1 connection make sure its a Y and not a T
Title: hooking up vacuum fuel pump
Post by: Jerry Hall on April 24, 2015, 09:53:16 PM
The fuel pressure and volume of the Mikuni pulse pumps depend upon the engine RPM, the length and diameter of the pulse line and maximum and minimum pressure the crankcase experiences.  I have seen some of these pulse pumps make as much as 7 PSI on some engines and not work at all when the pulse lines are too long.  Always to keep the pulse lines as short as possible.  I try to keep them less than 12" long.