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Swirl pot pump running all the time?
paublo999 - 25/7/10 at 03:49 PM

Hi All,

After a wee bit of advice.

Have installed a fuel swirl pot with Facet Posi Flow solid state pump to transfer the fuel from the main tank. I have an alloy 1.5lt swirl pot, with 4 6-AN connectors - Its all working fine apart from the lifter pump is not switching off when the swirl pot fills.

I have the copied the SBD config on the swirl pot (lowest to highest) -

1. lowest connection to fi filter/pump to engine
2. lifter pump feed from main tank
3. return from fi fuel regulator
4. overflow return to main tank.

Essentially I have created a race track setup and the pump runs all the time. Any suggestions for getting it to shut off when the swirl pot is full? Some sort of inline sensor? I had been told that if I create a slight restriction in the pipe going to the fuel tank it would shut off. This isnt the case.

I went for the facet solid state as I thought it would last a bit longer if it did run dry occasionally at the end of longer runs.

Any suggestions?

Cheers
Paul

40inches - 25/7/10 at 03:59 PM

You have effectively got an open pipe running from the pump, I would think that you would need a very small restrictor in the return hose, a .8mm MiG nozzle should do it

paublo999 - 25/7/10 at 04:01 PM

I tried to compress the return line with a pair of mole grips and the pump just ran quicker like it was fighting against the pressurised swirl pot. I had expected it to stop. Now wondering if the Facet pump as a pressure sensor inside it?

Anyone else done this?

interestedparty - 25/7/10 at 04:08 PM

quote:
Originally posted by paublo999
I tried to compress the return line with a pair of mole grips and the pump just ran quicker like it was fighting against the pressurised swirl pot. I had expected it to stop. Now wondering if the Facet pump as a pressure sensor inside it?

Anyone else done this?




That's not fighting, it was speeding up cos ther was no load on it. Same thing with a vacuum, put your hand over the end motor speeds up.

r1_pete - 25/7/10 at 04:10 PM

I built a swirl pot with an SU carb lid and float in the top, so, like with a carb, the pump shut off when the pot is full.

I still have it somewhere, hopefully it'll go back into service on the Jag, I will put a pic up when I find it.

omega0684 - 25/7/10 at 05:38 PM

surely you want the pump running all the time so that the lifter pump is constantly filling the swirl pot to stop fuel surge.

if you have it set up your way, when the swirl pop is full and the pumps off, how is it going to turn itself back on again to fill it back up when the swirl pop runs empty.

IMHO you want the swirl pop full all the time. anything that isn't used is simply returned to the main tank

paublo999 - 25/7/10 at 05:58 PM

I obviously didn't put enough thought into the pump side of the system. I had hoped for a place where if the car was idling and not using much fuel the pump would slow down or stop like on my old fireblade carburated setup.

Plus the pump is really noisy

Cheers

paublo999 - 25/7/10 at 06:00 PM

I might just pick up an old bike pump as they are really quiet and not worry about it. If there was nice inline sensor of some sort that would be ideal. Doesn't sound like it though.

Cheers

scudderfish - 25/7/10 at 06:14 PM

One advantage of keeping it running is that you will get a constant supply of cool fuel into the pot and less likely to suffer vaporisation.

snapper - 25/7/10 at 06:40 PM

The lift pump is doing it's job, it tries to fill up the swirl pot but as the swirl pot has a return to the tank it will never need to stop.
If it is noisy and I suggest you won't hear it unless you are stationary then some sound proofing would help

fatbaldbloke - 25/7/10 at 08:14 PM

What you have is fine. The way to slow it down a bit is put a restriction in the return to the fuel tank, about 0.8mm as mentioned is usually close. It should run all the time.

paublo999 - 25/7/10 at 08:40 PM

Don't have access to a welding nozzle
Any suggestions on what to use? I have used braided hose with an6 fittings throughout.

Thanks for the posts.

Cheers

paulf - 25/7/10 at 08:47 PM

I have a facet red top feeding my swirl pot and that is very noisy but never hear it when in driving.I put a .8 MIG nozzle in line but it still ticks away .If you dont have access to a MIG nozzle then a short length of threaded rod or an off cut from a bolt that is a slide fit in the hose would probably do.
Paul

fatbaldbloke - 25/7/10 at 09:33 PM

quote:

Don't have access to a welding nozzle


You can buy them at any tool shop, or even Halfords. Shouldn't be more than a couple of quid, fiver at the most.

paublo999 - 25/7/10 at 09:36 PM

Thanks guys. Will try the welding nozzle from halfrauds

Cheers

atspeed racing - 26/7/10 at 05:05 PM

We sell a very nice fuel pump that is super quite and reliable.
It comes complete with a micro filter, short length of hose, a mounting bracket and hose clip.
I cant stand the noise of the solid state pumps. Drives me mad

beaver34 - 27/7/10 at 06:47 AM

as if you going to hear it with a bike engine in the front anyway!

paublo999 - 27/7/10 at 07:35 AM

Haven to agree with atspeed. The solid state pump is stupidly noisy. Will swap it out when I have more time.

Cheers