Did all AU's have the same fuel pump?

5.0 ED · 10-09-2008, 02:15 AM

I've got some fuel pressure issue's, its a new VDO pump, new filter everything. At 4000rpm up, my fuel pressure drops below 20psi, on the dyno we were getting 180kw's top with a/f ratio's 13.5-14.0 cause of dropping fuel pressure, so i figure i have like 200rwkw's max if mixtures corrected, but there's no way the standard pump will keep up with it, so im wondering did the factory strokers etc. still use the same pump? Are the standard pumps this bad, or is it maybe i just got a dud? or need to start checking for a crushed fuel line or something.

TheSly1 · 10-09-2008, 08:33 AM

Check the voltage to the pump... if not enough you might need to power it via a relay...

Either pump is not working properly or not enough voltage.

OH also replace fuel filter... as if blocked this will effect flow..

5.0 ED · 10-09-2008, 09:28 AM

new fuel filter, was thinking possible low voltage myself after posting this, or that when i had the tank out i may have somehow squashed the 2 hoses together or something.

What i'm really wanting to know thou is what sort of power the standard pump is capable of supporting.

**Stav** · 10-09-2008, 04:00 PM

Quote:

Originally Posted by 5.0whiteaughia

new fuel filter, was thinking possible low voltage myself after posting this, or that when i had the tank out i may have somehow squashed the 2 hoses together or something.

What i'm really wanting to know thou is what sort of power the standard pump is capable of supporting.

ok...firstly pressure is maintained by
Your fuel regulator and then the available flow from the pump .is your regulator faulty? Check your pump? do a flow test to see if it is ok. What is the pump rated to? If it is a much bigger than stock you may need to upgrade the wiring.
Hang on a second...what fuel line did you use to connect the outlet to the fuel pump assembly?

StealthAu · 10-09-2008, 06:40 PM

So back on the question asked in the title, does anyone know if all fuel pumps are the same from factory in the au's?

RG · 10-09-2008, 06:49 PM

Don't know about the pumps but the regulators are different, the 220 had a higher pressure. An easy fix with a 10mm socket, a hammer and some delicacy.

MADED-6 · 10-09-2008, 07:36 PM

have you done this russel?
cheers josh.

RG · 10-09-2008, 07:45 PM

Quote:

Originally Posted by MADED-6

have you done this russel?
cheers josh.

I did it to my EL and Herrod had done it to my XR before I bought it.

**Stav** · 10-09-2008, 08:42 PM

Quote:

Originally Posted by StealthAu

So back on the question asked in the title, does anyone know if all fuel pumps are the same from factory in the au's?

No.They are not.

5.0 AND 4.0 LITRE AU sedan pump

FLOW IS 2.6 LITRES PER MINUTE OR 156LITRES PER HOUR.

wagon and utility is
FLOW IS 2.4 LITRES PER MINUTE 144 LITRES PER HOUR.

**Stav** · 10-09-2008, 09:32 PM

Figures quoted at 300kpa

5.0 ED · 11-09-2008, 01:02 AM

ok thanks stav, question answered, and no way is my pump delivering that, considering completely blocked off with a pressure gauge on it, engine not running pump turned on by bypassing relay tonight, it tops out at 38psi, and if i start the car, with the extra couple volts gets up to around 55psi, so i've narrow'd it down that its not a blocked line or anything like that cause i'd still get higher pressure with system completely blocked off, and would just have reduced flow, so it leave's me with 2 other possible causes, 1 being low voltage at tank, and the other could be just that the pump is just crap.

I had also previously noticed that on my car with fuel pump running the fuel pressure is the same as when its not running, on our other car the fairlane, when the pump is running it is about 2psi higher than when its not.

Anyway i'll pull the cover off and check the voltage at the tank tomorrow.

So now if it is a faulty pump, what does everyone recommend? I've been thinking walbro, but apparently there's a bit of modding to get them to fit, anyone know?

**Stav** · 11-09-2008, 08:12 AM

Quote:

Originally Posted by 5.0whiteaughia

ok thanks stav, question answered, and no way is my pump delivering that, considering completely blocked off with a pressure gauge on it, engine not running pump turned on by bypassing relay tonight, it tops out at 38psi, and if i start the car, with the extra couple volts gets up to around 55psi, so i've narrow'd it down that its not a blocked line or anything like that cause i'd still get higher pressure with system completely blocked off, and would just have reduced flow, so it leave's me with 2 other possible causes, 1 being low voltage at tank, and the other could be just that the pump is just crap.

I had also previously noticed that on my car with fuel pump running the fuel pressure is the same as when its not running, on our other car the fairlane, when the pump is running it is about 2psi higher than when its not.

Anyway i'll pull the cover off and check the voltage at the tank tomorrow.

So now if it is a faulty pump, what does everyone recommend? I've been thinking walbro, but apparently there's a bit of modding to get them to fit, anyone know?

Mate...if you can remove the fuel line and have it feeding into a 2 litre coke bottle.Bypass the relay and watch the fuel flow.It should fill the bottle with a solid stream of fuel..no drips n drabs.If its drip/drabs the pump is definately the culprit.
When I installed my walbro 600hp pump in searching for a leanning mixture I found that earthing to the body the pump made it spin faster. I am suspect in your choice of pumps too.All the ford au's have ac delco fuel pumps that I know of. What is the part number of your vdo pump?

5.0 ED · 11-09-2008, 10:00 AM

hmm so sounds like they may suffer a bit of earthing problem then, no idea of part number off pump, i purchased it off ebay, but the one that came out was VDO as well, feed out of fuel isn't in drib's and drabs, but with pressure reg on, it comes out of return in dribs and drabs.

But come to think of it with engine idling my lights pulsate with lope with cam, so thats probably why.

I purchased a fuel reg off a guy off ebay yesterday, i hook it up and bench tested it and it doesn't regulate, pressure increases and decreases with flow so im taking it back tomorow, just another show of how my luck if going with this fuel supply problem. Maybe i need to stop buying off ebay?

On the positive side of things i have done 350km's since filling up, and done a lot of short trips and i still have slightly over 1/2 a tank on the gauge

**Stav** · 11-09-2008, 02:54 PM

Quote:

Originally Posted by 5.0whiteaughia

hmm so sounds like they may suffer a bit of earthing problem then, no idea of part number off pump, i purchased it off ebay, but the one that came out was VDO as well, feed out of fuel isn't in drib's and drabs, but with pressure reg on, it comes out of return in dribs and drabs.

But come to think of it with engine idling my lights pulsate with lope with cam, so thats probably why.

I purchased a fuel reg off a guy off ebay yesterday, i hook it up and bench tested it and it doesn't regulate, pressure increases and decreases with flow so im taking it back tomorow, just another show of how my luck if going with this fuel supply problem. Maybe i need to stop buying off ebay?

On the positive side of things i have done 350km's since filling up, and done a lot of short trips and i still have slightly over 1/2 a tank on the gauge

Your pump is shagged.Go to the wreckers ,get a cheap second hand jobbie and try it. Dont do your head in..its highly likely stuffed.

**Stav** · 11-09-2008, 04:26 PM

Quote:

Originally Posted by Stav

Your pump is shagged.Go to the wreckers ,get a cheap second hand jobbie and try it. Dont do your head in..its highly likely stuffed.

I can vouch for the sard adjustable fuel regulator. I have had mine for 14months and its perfect. I also have a spare with gauge for trouble shooting.

5.0 ED · 12-09-2008, 02:50 AM

Anyway further to my low fuel pressure research i did discover that I, have been partly to blame, at the fuel pump plug, 3 wire's soldered, 1 wire twisted together, here's me (Mr electronics engineer), with a twisted together wire, fully corroided, and a slight voltage drop.

Nothing like admitting that yes SIR, me Mr, 4 years at uni, 9 years in practice has well F'd Up.

So anyway i fixed it all, made it all nice and neat, added an extra earth line and so on, check voltage, nice and high, and yep guess what, it's improved, but the problem is still there. And fuel pressure is stilll dropping, just not as bad, las in at 4000rpm i'm down to 23psi now.

So anyway i have decided on an inline fuel pump to solve my misteries............. Can't 100% remember the number but it involved a 44, ;), so i'm gonna put a bosch 044 inline with my current VDO pump, and hopefully i shall have low fuel pressure no more.

5.0 ED · 12-09-2008, 02:52 AM

oh a maybe a smack with a 10mil (thanks russell

Shall sort me out

**Stav** · 12-09-2008, 09:23 AM

044 is good for 700 hp. good choice.Just becareful..if the first pump dies then the second wont really help. i think you would do better to get a better primary pump. Even my internal walbro has held up well .

RG · 12-09-2008, 09:41 AM

Quote:

Originally Posted by Stav

044 is good for 700 hp. good choice.Just becareful..if the first pump dies then the second wont really help. i think you would do better to get a better primary pump. Even my internal walbro has held up well .

Same here, my Walbro 255 in tank is all that is supporting mine and it gives no problems.

5.0 ED · 12-09-2008, 09:44 AM

yeah there's kind of a problem in getting into the tank, there was an incident a long time ago involving a hayman reece towbar end going thru the top of my tank cause i had left the metal cover off, so now the top of the tank involves a lot of epoxy and bog in it, so i really want to just stay clear of it.

Either way if the intank pump dies, i'd be left on the side of the road, so i don't see it really mattering that much, and if it does die then i suppose i'll have to just pull the tank out and replace the whole tank with a s/h unit.

I figured with pump that i want to be covered with enough flow for future mods, now when i hook it thou i suppose i'll probably have a fuel reg that can't handle the flow?

RG · 12-09-2008, 09:48 AM

Fuel reg will be fine for the moment, mine is, and besides any excess just goes down the return line.

5.0 ED · 12-09-2008, 10:21 AM

ok cool thanks for that.

5.0 ED · 17-09-2008, 01:06 AM

Ok actually got around to be bothed to fit extra pump, so after playing around last time with the wiring and getting a little more power to standard pump, my afr's full throttle under 4000 where at 12.8, fuel pressure on gauge was 39psi (had already had a slight knock with a socket), but up top it was still dropping pressure.

So i put on new pump now, 39psi all thru the entire rev range, afr's are now 10.5 full throttle thru the whole rev range, so now im a little confused, if it was at 39psi before below 4000, and now its 39psi there as well, why would low rev mixtures change so much?