questiona bout Fuel pump

[EvoDre]

i have a kx250 motor on a shifter kart frame. my issue that i am having is that my gas tank is in the front so it is not gravity fed. so i was wondering if there is a fuel pump out there that i could use, or that someone could recommend. electrical or vacuum operated. thanks a lot in advance.

If someone is selling one on here that would be even better!

 

[Doc Sprocket]

A lot of people use Mikuni pulse (vacuum) pumps. Alternatively, you could use an electric pump sourced from a motorcycle, or even one designed for a carbureted car.

 

[fowler]

That about covers it
Either a vacuum pump which requires attaching a fitting to the valve cover

Or using an electric pump

Ones for a car or bike are usually a pain to use because they are in tank mounted or controlled by the cars ECU

U can buy a generic pumps that just require a 12 volt supply then lines running to and from it
If u simply connect the pump straight to the carb then the pump will flood the carb
U require a surge tank that is a smaller tank over the carb of maybe 1/2 litre
It allows u to gravity feed the carb but mount the tank else where

U must a set of lines and two tanks
First a line from the tank to the pump
The pump to the bottom of the surge tank
3/4 of the way up the surge tank there is a line returning to the tank
From a 3rd fitting at the bottom run a line to the carb
The surge tank should be as big as possible to reduce the chance of flooding

If u wanna get technical then u could mount a cut out switch by mounting a switch in the top of the tank

Clearly a vacuum pump is far simpler

 

[Doc Sprocket]

An electric pump may not need to be that complex. Some inline auto types develop 5 or 6 psi max, and some can be dialled down. Most carb fuel inlet valves are spec'd at 5psi pop-off, so you could just restrict the fuel ressure lower than that. A regulator may be an option, too.

Also, having a Tee fitting at the carb, with a valve and a return line to the main tank could allow you to manually regulate the incoming pressure. Opening that valve would allow more fuel to bleed back to the tank and lower the delivery pressure.

 

[jandj]

I'd go with a vacuum pump, much simpler. A fitting, a pump, some hose and clamps....that's it. Just about any kart parts place will have what you need and it's not expensive.

 

[Doc Sprocket]

Agreed.