no fuel?

[greg1.4]

got a problem in my twin carb'd nova..

its a standard spi fuel tank/pump and lines i am running..i have the pump on all the time (well on a switch)

but now i dont have any fuel coming through..the car just cut out one day.

i also cant hear the pump buzzing away anymore..it used to buzz when the ignition came on.

i havnt got a clue about fuel pumps/relays etc so if anyone could tell me where to start it would be great..

cheers

Greg

[Adam]

Check the switch/switch wiring.
I assume your just switching 12v to the fuel pump?

[saloonwoody]

the pump wont have had enuf flow so you prob ran it dry and its seized !
you need a bigger external pump .

[Adam]

Hes running carbs....
Spi pump is perfectly man enough for the job

[meritlover]

the pump wont have had enuf flow so you prob ran it dry and its seized !
you need a bigger external pump .

im assuming this is not the case and that it was installed into a return line through a relief regulator.

[saloonwoody]

Hes running carbs....
Spi pump is perfectly man enough for the job

well i ran a 1.8 on a single carb and my spi pump was not enough :confused:

[meritlover]

well i ran a 1.8 on a single carb and my spi pump was not enough :confused:
:wtf:

[mowgli]

When will people ever learn... a carb needs low flow & low pressure fuel supply, basically it just needs the fuel getting there.

spi needs higher flow & pressure

mpi needs much higher flow & pressure.

the spi pump & reg. needs replacing with a facet red top pump or similar.

[Adam]

The Spi pump is PERFECTLY good enough, as long as you've got a regulator fitted.
It flows more than a facet! lol

It needs a regulator, and a return line, because it works at about a bar, when carbs need about 3psi.

I ran my t40d engine for months on the spi pump.

[mowgli]

And I am saying that you only need to fit a carb pump to run carbs.......
if your car does 30mpg at 60 mph it needs 2 gal/h(9l/h) or 2.5ml/sec to keep the carbs fed, so if we give a safety margin of 2 we are looking at 1teaspoon per second...............
A fuel injection system relies on a continual pressurised fuel feed passing a point where a valve releases a timed amount of pressurised fuel into the intake.

The SPI pump is still TOO powerful for the job, & all carbs have some sort of float chamber with a cut off valve which stops the flow of fuel... deadheading a pump is one of the best ways to break it.

[Adam]

Hence my comment about having a regulator and return line.
The return line being very important.

[meritlover]

Hence my comment about having a regulator and return line.
The return line being very important.

here here! the flow will be the same as the engine is still burning a simelar volume of fuel, but seeing as the pressure is reduced to the carb so much the pump will have to work less hard to maintain the pressure than it would in an SPI engine.

the regulator must not be installed the same as the injection engine (controlling backpressure) as the high volume of the pump will probably over come the needle valve all to easily and flood it. the return and regulator must be installed up-stream of the carb.