hi i have a fuel pump problem
i have zetec running gsxr throtttle bodies with megasquirt i had been using a fireblade carb fuel pump but it would only run when at 1 bar but i could drive it to where i store it
so i bought a fuel injection pump fitted it, the pump seems to run all the time unless you clamp the hose then it turns off
i have had to turn the tick over up to make it run its putting out a lot of smoke if i turn the pump off the car runs better
so what have i dont wronge

[Edited on 16/5/11 by doddy]

do you have a fuel pressure regulator?

Injection pumps don't generally work the same as those nice mitsubishi bike engine carb pumps. They don't self regulate (except the in-tank ones which can).

Search on here for "fuel pressure regulator" and you will find a diagram of how it should work.

hi yes i have a fuel pressure regulator it does not do anything with this pump only the other pump it would only run well set to 1 i need it to be set a 3 for injection

You need an injection regulator which will have a return to the fuel tank (or swirl pot)
(Sounds like you just have a simple carb type regulator which won't do for injection).

hi i have this regulator
SYTEC FUEL PRESSURE REGULATOR 8MM ADJUSTABLE | eBay UK

is this no good i have a return to tank and thats working fine

[Edited on 16/5/11 by doddy]

The regulator that you show says 1-5 psi.

Normally injectors run at about 43.5psi (approx. 3 atmospheres).

Perhaps you could post a photo of how it is all plumbed as I think this might be where the problem is, but a photo would clear things up.

Matt

i think you maybe right i need one of these

Precision Fuel Pressure Regulator Injection / Turbo Car | eBay UK

i have it pumped as tank with in tank swirl pot - pump- filter- fuel rail- regulater- return to tank

[Edited on 16/5/11 by doddy]

I haven't got one of those. I bought a cheap McGill one, which I chose to replace with a FSE AIR004 (actually made by Malpassi), that I am hoping I can be more confident of.

It isn't clear whether the one you show is adjustable, or at what pressure it is pre-set. 3atm is something of a standard, although some rails are a bit higher.

What kind of pump do you have?

As said the regulator should be set to give a continues pressure of 3-4bar in the fuel rail at all times. so fuel goes(in my case) from tank to pre pump filter - fuel pump -post pump filter - fuel rail - regulator - return to tank. The regulator needs to be set to allow the pressure to be high enough to allow enough fuel to flow when the injectors open, but if the pressure needs to be much above 3.5-4 bar then you will need bigger injectors. The fuel pump will be running all the time the engine is running unlike the on/off of a carb pump.


[Edited on 16/5/11 by zetec]

[Edited on 16/5/11 by zetec]

[Edited on 16/5/11 by zetec]

i have a pump very similar to this
MERCEDES FUEL PUMP 260E 300CE 300E 300SE 300SL 300TE | eBay UK

You need an injection regulator and a fuel return line.

Injection regulators bleed excess pressure in the fuel rail back via to the return to the tank or swirl pot, this is important to keep the pump cool.

Very important not to clamp the outlet from an injection pump it needs fuel flowing through it to cool it, stopping up the outlet is a very quick way to knacker the pump.

ok cheers for everyone input i will buy new injection regulator and see how that goes