044 Pump Issue

[SirRacer]

Changed relay and problem is still there. The pump is also seeing 13 volts at present.

How much is one of those coolers?

[psi]

Think outside box alittle bit..

low fuel consumption from the engine, same fuel pressure and volume from the pump = most of the fuel is getting heated in the fuel rail and is then getting sent back to the tank (over pumped), recycled and pumped up again. On a nice cruise the fuel gets 'hot' and the problems unfold. Its not about the pump, more about the the flow rate and the engine just doesn't require that much fuel at very light throttle, so the fuel reg just bypasses it and sends it back.

a smaller pump would have less return flow, but wont have the flow for max engine output. that make sense?

[SirRacer]

Ok i fully understand the point, I just cant quite comprehend that out of all the 044's running externally in cars today that all these people are having to run a fuel cooling setup to solve the overheating problem?

That said im going to track down a oil cooler and do some mods to it and at least try that option.

Would people suggest mounting it in the boot and running a fan over it or mounting it somewhere under the car?

Edited December 20, 2008 by SirRacer

[Guilt-Toy]

ahhhh ANOTHER one of my threads being raised from the dead...

I can tell you for sure that the issue does exist... There would be many people having the same issue that are not aware of their cars that they do not think its a problem and they just live with it...

I PM'd you my phone number.. call me tomorrow after 10pm and i will chat to you about it. You definaty need a fuel cooler OR a voltage droppage configuration that will drop the pump flow on low rpm cruise loads.

[gibbau]

On the subject of suitable coolers;

I have a just jap oil cooler core (30 row I think, its massive). I'm not going to use this for engine oil as I now want to get a genuine oil cooler kit for peace of mind. Would this be suitable to use as a fuel cooler?

Or, would it be ok to get a second hand tranny cooler and use that?

something like this: http://cgi.ebay.com.au/Oil-transmission-co...A1%7C240%3A1318

My plan is to mount it across the spare wheel well, with a thermo ontop next to my surge tank. Because the core is so large, will it have any problems pumping the fuel through the core and up into the surge tank?

Edited December 20, 2008 by gibbau

[Guilt-Toy]

On the subject of suitable coolers;

I have a just jap oil cooler core (30 row I think, its massive). I'm not going to use this for engine oil as I now want to get a genuine oil cooler kit for peace of mind. Would this be suitable to use as a fuel cooler?

Or, would it be ok to get a second hand tranny cooler and use that?

something like this: http://cgi.ebay.com.au/Oil-transmission-co...A1%7C240%3A1318

My plan is to mount it across the spare wheel well, with a thermo ontop next to my surge tank. Because the core is so large, will it have any problems pumping the fuel through the core and up into the surge tank?

hey bud

that oil cooler you linked to ebay will be PERFECT for the job.. the just jap oil coolers aint too bad ... i use one.. you just need to make sure they dont leak and sometimes you need to mod them.. in my case i just got the fittings put into a lave and removed the ring for the o-ring and replaced them with a copper washer.. NEVER leaked again and it works a treat!!!

get tha oil cooler from ebay and use that as a fuel cooler, its much bigger then mine was and it will work great! i promise you this... use your just jap cooler as they aint too bad as long as they dont leak, if it does leak then DONT replace it just fix the leak.. then they work pretty damn good!

Good luck with it.

[gibbau]

hey bud

that oil cooler you linked to ebay will be PERFECT for the job.. the just jap oil coolers aint too bad ... i use one.. you just need to make sure they dont leak and sometimes you need to mod them.. in my case i just got the fittings put into a lave and removed the ring for the o-ring and replaced them with a copper washer.. NEVER leaked again and it works a treat!!!

get tha oil cooler from ebay and use that as a fuel cooler, its much bigger then mine was and it will work great! i promise you this... use your just jap cooler as they aint too bad as long as they dont leak, if it does leak then DONT replace it just fix the leak.. then they work pretty damn good!

Good luck with it.

Thanks for your input I've just heard way too many stories about leaking lines destroying engines and whatnot from china kits.

I'm a fitter and turner apprentice so it's no drama to mod the o-ring.

I'll give it a go and keep an eye on it

[discopotato03]

Hi all , I just read through this whole thread and a possibly silly idea occured to me .

Some late model cars don't have a return line from the engines fuel rail at all and I had to ask a long time mechanic mate of mine how such a system could possibly work .

He claims that they do actually have a pressure regulator and return but its close to the pump so possibly in tank ?

So me thinks what would happe on a conventional fuel injected car like an RB powered Skyline if the fuel pressure regulator was moved to a "T" piece a little short of the rail itself .

My thinking is that the heat is conducted from the manifold to the rail (or hot ngine bay) so if you could have a return supply system with one side of the T heading to the rail and no rail return do you get around the thermal issues .

The unknown is how hot would the fuel in the rail itself gets and what if anything the manufacturers do to get around it if it is a problem .

One things for sure , if in a hot state you stood on it the supply of fuel comming down the line should be cool once that in the rail had been used .

If this system is workable it should be reasonably cheap as all you'd be doing is moving the reg and adding a T piece and short runs of new EFI hose .

Thoughts ?

Cheers A .

[Guilt-Toy]

i mounted my fuel cooler back in the car today. in a different spot so i can run a air con condensor fan as well.

will connect it back up to the fuel system next week, it just needs to be connected all the fuel lines have been run etc etc

[Fastrotor]

The simplest way would be to reinvoke the factory system of lowering the pump voltage when not needed... this is obviously one of the reasons the factory do it in the first place, and we all go and rip it off. So way not use a spare output to controll your own setup of a relay and resistor. You could experiment with what size resistor will maintain the flow needed below your chosen rpm (since bosch flows more, it may need less volts at low revs than the stock pump needes to maintain pressure) ...

A correctly working two stage system is the best soloution , no coolers required.

Gary

[unique1]

my car also had these issues running twin external 044s and 2 in tank pumps feeding the surge tank. Not too noisy until about 45 min into a drive on a hotday and the 044s would whine like crazy until it cooled down and then they are fine again. Im gonna look into the fuel cooler setups now, just wondering what sort of dimensions are these coolers u guys are using?

[Guilt-Toy]

my car also had these issues running twin external 044s and 2 in tank pumps feeding the surge tank. Not too noisy until about 45 min into a drive on a hotday and the 044s would whine like crazy until it cooled down and then they are fine again. Im gonna look into the fuel cooler setups now, just wondering what sort of dimensions are these coolers u guys are using?

i just used a small tranny oil cooler, its not very big but it does help the system go 3 times longer before the pump starts to complain.

[Fastrotor]

For the record, my 040 intank has done the same.... noisy as hell after a dyno session and slow drive home..... its been quiet when cool. i guess since its submerged its cooled for longer, however the dyno session heated up the fuel alot .

I'll wire the two stage back in, modified of course to provide full power when switched to direct.

Gary

[Guilt-Toy]

if you wire the 2 stage back in, will it be enough power to run 2 x high pressure pumps?

[unique1]

so whats the benifits between using an ally oil cooler or proper copper fuel cooler or tranny cooler? any differences? i assume the fuel cooler is made for the high pressure side, they look like a copper tube in an S shape and fins around them. Ive even considered the moroso fuel cooler setup as well, but they are pricey compared to other options.

[Swiper the Fox]

ive got a small Earls oil cooler that will do the trick

[SirRacer]

Have you heard of this sort of issue being common? Spoke to a Race Car builder yesterday who says he hasnt come across this problem at all when building RB powered cars. Another two mates have 044 powered setups running exactly the same system as me with no problems at all. All rail fuel was being returned back into the surge tank.

I wonder if its just the way the fuel lines are run or something in the RB's?

[Fastrotor]

if you wire the 2 stage back in, will it be enough power to run 2 x high pressure pumps?

Obviously not the std setup, but a custom setup would work fine. I'm about to swap out the 040 for a walbro over the chrissy break, so i will have a look at the wiring and work out a way to wire an external two stage setup triggering off the stock one and get back to you , with a drawing and all if anyone is keen.

Obviously i can't say definitively what voltage the "low" setting has to be, until i get an idea what each pump needs to work at minium load setting, then i can reccomend a resistor to suit.

I'll come back with some definate info later on. And if there is interest i can whip them up to ease install for those not into electronics/ electrical etc .

Gary

[Guilt-Toy]

let us know what you come up with.