My Swirl Pot

[Bill Blue]

For the last ten years I have had the fuel pump mounted on bottom of the trunk floor, gravity fed from the stock fuel outlet on the Series V car. Bypass fuel was routed to the right hand fuel tank. It worked fine except when fuel level was low and making long left hand turns as found on interstate interchanges. All the fuel would find its way into the the right hand tank, starving the engine for fuel. This is my attempt to solve that problem

The tank is constructed of 3 1/2" exhaust tube. It is 4" long and holds 26 oz. The hose barbs are 5/16", threaded and soldered in place. The side hose barbs are inserted into the tank on a tangent in order to induce swirl. The pump inlet hose is fuel injection hose and will be clamped. The tank mounts under the bottom of the left rear seat in the area occupied by the battery on the other side. There is plenty of room and the bottom of the fuel pump hangs down only to the top of the leaf spring. The pump mount is machined out of a slab of 1" aluminum.

The tank is functionally complete. It has to be sealed (POR 15 tank sealer) and painted.

Bill

 

[Barry]

Bill,

I was looking at your "swirl pot" post with the embedded pictures.

First, the pictures disappeared. Then the post disappeared.

No idea what is going on, but something is wonky with your post, my computer, the website or .....

 

[Bill Blue]

I screwed up the initial post. I decided the pictures I had attached were terrible and took another set. I then discovered there is no obvious way to remove photos from a post. I finally deleted the post and made another one, using the new pictures. The post has survived but the photos have not. I have no idea how to insert them. I'll try to attache them here.

Bill

 

[PROCRAFT]

Maybe you could have put a one way valve on the crossover tube and picked the fuel up from the side you returned the fuel ?

 

[Barry]

Bill,

Trying to make sure I correctly understand which connection goes where; please advise based on the colored circles I added to your picture.

Blue

Red

Green

Pink​

 

[Bill Blue]

Barry,
Blue returns fuel to the tank
Red receives excess fuel from the engine
Green receives fuel pumped in from the stock fuel outlet
Pink is high pressure fuel to the engine

There will be a low (4 psi) pressure, 30 gph pump supplying filtered fuel to the Green hose bib.

Procraft, I was sending return fuel to the tank that has the filler, so the valve would not allow the other tank to fill. The idea would work if the return was to the other tank, but it does not allow the fuel system to expel any air it might pick up. The swirl pot expels air with the excess fuel. A check valve has several problems that I won't go into. I think that "easy to say but hard to do" might sum it up.

Bill

 

[PROCRAFT]

Barry,
Blue returns fuel to the tank
Red receives excess fuel from the engine
Green receives fuel pumped in from the stock fuel outlet
Pink is high pressure fuel to the engine

There will be a low (4 psi) pressure, 30 gph pump supplying filtered fuel to the Green hose bib.

Procraft, I was sending return fuel to the tank that has the filler, so the valve would not allow the other tank to fill. The idea would work if the return was to the other tank, but it does not allow the fuel system to expel any air it might pick up. The swirl pot expels air with the excess fuel. A check valve has several problems that I won't go into. I think that "easy to say but hard to do" might sum it up.

Bill

Speaks volumes for this deal?

 

[Bill Blue]

It all depends on your design priorities. BTW, does your tank have a built in swirl pot?

Bill

 

[PROCRAFT]

It all depends on your design priorities. BTW, does your tank have a built in swirl pot?

Bill

Don't think it needs a "Swirl Pot" this is a FI tank with a well, 100 gph in tank pump/pre filter post filter on the engine side.

 

[RootesRacer]

Barry,
Blue returns fuel to the tank
Red receives excess fuel from the engine
Green receives fuel pumped in from the stock fuel outlet
Pink is high pressure fuel to the engine

There will be a low (4 psi) pressure, 30 gph pump supplying filtered fuel to the Green hose bib.

Procraft, I was sending return fuel to the tank that has the filler, so the valve would not allow the other tank to fill. The idea would work if the return was to the other tank, but it does not allow the fuel system to expel any air it might pick up. The swirl pot expels air with the excess fuel. A check valve has several problems that I won't go into. I think that "easy to say but hard to do" might sum it up.

Bill

Looks legit though I would not suck unfiltered fuel from the bottom of the pot into a HP/gerotor pump.
You could LP pump into the swirl pots bottom port and then take the green output into the HP pump inlet port. In short swap the bottom and green port lines.

OEM setups have a sock on the pump inlet so the crud that ends up in the bottom of the tank doesnt damage the HP pump.

 

[Bill Blue]

Fuel from the tank going into the swirl pot will be filtered.

Bill

 

[Barry]

Bill,

In addition to a filter between the tank and the low-pressure pump, I would put a filter between the swirl pot and the high-pressure pump. As Jarrid noted, high-pressure fuel pumps don't handle trash well. For that matter, neither do injectors or pressure regulators, so many systems also have a filter after the high-pressure fuel pump. Maybe overkill, but filters are cheap; it's all the other stuff that's expensive.

 

[PROCRAFT]

Bill,

In addition to a filter between the tank and the low-pressure pump, I would put a filter between the swirl pot and the high-pressure pump. As Jarrid noted, high-pressure fuel pumps don't handle trash well. For that matter, neither do injectors or pressure regulators, so many systems also have a filter after the high-pressure fuel pump. Maybe overkill, but filters are cheap; it's all the other stuff that's expensive.

Most if not all FI systems have a pre and a post filter like I noted in my post as you say they don't like trash.

 

[DanR]

Good discussion! Beginning to understand the concept. I think

 

[DanR]

In short swap the bottom and green port lines.

Rootes, Can you clarify for this Olde Dummy what you mean by bottom and Green ? Which is the bottom?

 

[Barry]

See post # 5.

 

[RootesRacer]

Fuel from the tank going into the swirl pot will be filtered.

Bill

You may be assuming that your return fuel is clean and free of crud. I would not assume that.
Rubber deteriorates and solids fall out of solution as the volatiles evaporate.
Also HP fuel pumps shed "needles" that may make it past the HP filter and come back around the the fuel pot via return fuel.

 

[PROCRAFT]

You may be assuming that your return fuel is clean and free of crud. I would not assume that.
Rubber deteriorates and solids fall out of solution as the volatiles evaporate.
Also HP fuel pumps shed "needles" that may make it past the HP filter and come back around the the fuel pot via return fuel.

We all know how assume works!

 

[Bill Blue]

Not to worry - I found an incredibly slick solution. Should be able to post a photo of it Friday. I'll have a continuous supply of filtered gasoline and a usable trunk!

Bill

 

[PROCRAFT]

Not to worry - I found an incredibly slick solution. Should be able to post a photo of it Friday. I'll have a continuous supply of filtered gasoline and a usable trunk!

Bill

Not quite sure what useable trunk space has to do with your pot!