Fuel Starvation

[paul]

Hi All,
I've got a 200 bhp throttle bodied Zetec installed in my Rocket and had some fuel starvation issues from day 1.
We used a Webcon unit http://www.webcon.co.uk/shopexd.asp?id=12808 as it was met the spec and provides a nice integrated solution.
Turns out the pre-pump filter is very restrictive and collapses in on itself limiting fuel flow.


(Click for large view)

This was removed and replaced with a large external filter pre-fuel rail to protect the injectors at the expense of no filtering before the pump..

Here is a plot from a Llandow lap with the bottom graph showing in red the pressure drop with the filter and the black plot showing the filter removed.


(Click for large view)

I've had no problems with the fuelling system since doing this.

At Abingdon I suffered a total cut out of the fuel pump, which restarted 10 minutes later on its own accord.
For the rest of the day I saw occasional low fuel pressure warnings but no total failures.

First up, I could/should replace the filter as its now at least 1.5 years old and could be the cause.
I could have knackered the pump by not running a pre-filter.

I'm not convinced the filter would cause a total pump failure so suspect the pump is on it's way.

I really like the idea of an integrated solution rather than 2 pumps and an external swirl pot and found the Aeromotive Phantom looks like it would cope and is available from Demon http://www.demon-tweeks.co.uk/motorsport/fuel-tanks-cells/aeromotive-phantom-340-stealth-fuel-system (the 200 model)

Appreciate any suggestions anybody is able to make.

Thanks,
Paul

[CC Cyclone]

I have in the past tried to run FI without a pre-pump filter and it always ends in the pump getting jammed with crap from the tank. It usually results in the pump overheating. It once occurred when I was having a car mapped on the rolling road and Dave Walker gave me a telling off as he sees the problem over and over again.

I fixed it with a sytec pre-pump fuel injection filter from Merlin, not cheap but does the job and didn't restrict flow on my 250bhp duratec install in my previous ginetta.

[Iancider]

That sounds right to me - a better filter is required.  Thre is no vacuum formed because the whole system flow and return is at equaly pressure - it can only be the flow resitance through the filter that is causing it to collapse.  If it is a bigger cannister then it should have geater flow voume as well.  Good luck - Ian

[paul]

Following up on this with hopefully a conclusion...

I brought an Aeromotive Phantom 200 ; http://aeromotiveinc.com/products-page/stealth-fuel-systems/phantom-200-stealth-fuel-system/ from http://stores.ebay.co.uk/Torques-U-K who I can recommend based on this transaction!

I really wanted a neat intank solution without an external swirl pot and lift pump. This video sold me that it should be suitable ;

The specs looked better too;
Webcon 75L/H and 8.5A max at 12v @ 3.5 Bar
Aeromotive 189L/H at 13.5 V @ 60 psi (4.1 Bar)

A graph from a lap of Llandow from last September with Aeromotive in Red and Webcon in Blue


You can see a higher pressure is maintained, actual figures;

	Aeromotive	Webcon
Min	2.7	2.3
Max	5.6	5
Avg	4.1	3.8

New top of tank welded on to take level sender and new pump as it's smaller than the old one;


VDO tube level sender fitted;


Pump and hanger assembled to tank depth;


Basket;


Basket inserted and threaded mount/gasket;


Fitted (will change to right-angle pipe outlets for better pipe routing...);


I thoroughly recommend the Aeromotive kit, it's well thought out and so far on the 1st track day out performs the webcon and is also quieter as an added bonus.

Regards,
Paul

[Iancider]

It seems like a very sensible solution because the crud is usually lurking at the bottom of the tank.

Asking a simple question...  I take it you are running with a flow and return pipes because that is more about flow-rate than pressure.  So much fuel goes up to the engine that there is always enough and the excess returns to the tank.  That way it should never suffer from starvation (except for your filter blockage of course)

Regards
Ian

[paul]

Thanks Ian.

Yes, I am running flow and return, effectively, in order;

-Pump pre-filter
-Pump
-Filter
-Fuel pressure sensor take off
-Fuel rail
-Webcon Adjustable fuel pressure regulator
-Return to tank

The Aeromotive doubles the flow rate of the webcon pump so i've ticked that box based on your comments.

Regards,
Paul