Know anything about fuel pumps?

Know anything about fuel pumps?

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phillpot

Original Poster:

17,279 posts

190 months

Tuesday 3rd December 2013
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Just thinking out loud,

My TVR S3 has the Ford Cologne 2.9 EFI engine. Electric fuel pump is mounted near the rear wheel arch and gravity fed by a large bore (about 15mm) pipe from the bottom of the fuel tank.

The pump couldn't be in a worse place for getting covered in everything and should fuel pipe leak the whole tank will drain out.

So, had this idea, something like a Mondeo in tank fuel pump, solves both issues and the built in gauge sender may not swing around quite so wildly as the current one!

I imagine fuel pumps are generally capable of delivering far more fuel than the engine ever requires, so a pump from a 2.0l car should keepup with a 2.9?
The big question is, do modern engines run at around the same delivery pressure?

If you have knowledge and experience with fuel injected engines over the years I'd appreciate you input.

theshrew

6,008 posts

191 months

Tuesday 3rd December 2013
quotequote all
I don't know the answer to your question.

However I'm thinking you can get a 3L Mondeo ( or could not that long ago if you can't now ). If you find out if the pump is the same on the 3l and 2l surely that would give you the answer you require.


Auntieroll

543 posts

191 months

Tuesday 3rd December 2013
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Determine the delivery pressure/flow rate of your existing pump, specs may even be in the manual.
Compare specs of proposed replacement, if satisfactory, go for it.
I would have thought that the rail pressures would be fairly similar, the delivery rate will be OK if the engine the new fuel pump supplied had a greater power output than your V6.

Doctor Volt

336 posts

132 months

Wednesday 4th December 2013
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As Auntieroll has already stated - It is important that you check the pressure of the replacement pump against the original that you know is in good working order
Having done some searching it does look like a Mondeo 2L in tank pump will run very close to the same pressure as the original +5PSI, the problem arises when a figure taken from a test on another vehicle is not strictly true due to a possible blocked fuel filter, lines etc - My +5PSI is taken from a on vehicle test by a stranger
Should your replacement pump deliver a much higher pressure than the original there is a very good chance that the pressure regulator on your vehicle will not regulate correctly and your engine will not run as it should, a too higher pressure will very likely damage the regulator or the vehicle could even develop fuel leaks
It is very important that you use a replacement pump that delivers a pressure as close to the original as you can get, i feel it will be worth your while to speak to one of the technicians at your local Ford garage and ask them for the specification of a in tank Mondeo pump before you go any further
I would go about things a different way, have you considered how much work is involved in cutting the fuel tank, re-plumbing the rear end and sorting out the wiring to reach and fit the new location - should the fuel pump be badly corroded and in your opinion on it's last legs, why not get a good retro fit pump and then spend much less time making (pay someone to make) a cowl that will cover the pump to stop the weather biting it, you will be able to seal the pump in its cowl if it is a well made one, the other thing to do if you decide to go along with my way of thinking is to give the retro fit pump plenty coatings of primer and paint to be 100% sure that all is good

phillpot

Original Poster:

17,279 posts

190 months

Wednesday 4th December 2013
quotequote all
Doctor Volt said:
i feel it will be worth your while to speak to one of the technicians at your local Ford garage and ask them for the specification of a in tank Mondeo pump before you go any further
Was hoping there might be one reading this post!




Doctor Volt said:
have you considered how much work is involved in cutting the fuel tank, re-plumbing the rear end and sorting out the wiring to reach and fit the new location
Yes, I like a challenge.


Done a bit more research (and thinking) and a Range Rover pump is looking good, lot more metal and less plastic, should be easier to adapt wink

ch427

9,743 posts

240 months

Wednesday 4th December 2013
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you could relocate or fit another pump in the boot, you may still need to mod the tank outlet but shouldnt be too much of a problem.
I have my tank and pump in the boot area, its a cobra rep so not too far away from a tvr. I cant ever see the outlet pipe coming off but i do check it every so often.

S0 What

3,358 posts

179 months

Wednesday 4th December 2013
quotequote all
The standard inline EFi pumps run at the same pressure give or take and need to be gravity fed (that's why the feed pipe is so large)so HAVE to be below the tanks lowest point, i've retro fitted some in tank pumps into older metal tanks by cutting the mount (usually threaded but not allways) out of a donor tank and welded it into the old tank, i used ford ones as i seem to remember the fuel pick up was spring loaded to take into account of the differing depths of tanks it was fitted to, i've also rebuilt many an intank pump with a kit (usually you change the whole sender and pump/swirlpot in one unit) the kit is a generic pump with aplication specific parts so they are all the same, you also need to make sure the resistance of the fuel sender matches your dash wink

The general rule of thumb is CFI pumps are lower presssure than multipoint EFI and most EFi pumps run at near enough the same pressure (Turbo engines are a differant matter so stick to N/A donors if possable) to work on each other, i've used 1.8 cavalier pumps on 2.9 colognes, 2.0 EFi pumps on 2.9 24V ect ect

Edited by S0 What on Wednesday 4th December 22:41