In tank fuel pump???

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BellyDoc said:
Interesting, agreed!! :)

If the fuel pickup and the return are both in the sump, then in my assessment, it only depletes what it burns. This should last more than "seconds". Also, consider that the doodle obviously isn't a scale representation. Chicago is estimating a 1/3 gallon sump capacity, if I'm remembering correctly from a post above.

I'm not actually an advocate of the sump method anyhow... but in my assessment, the sump-with-drains only works if the level in the main tank is higher than the sump anyhow, negating the role for the sump. It's basically a sloped bottom tank.

As you can see in the post above, I'm a fan of the 4-corner Walbro pickup solution. It basically turns whatever corner is below fluid level into the sump.
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I agree the walbro system is nice, I like it but as I understand it is expensive. I agree the sump with drains is in a way a sloped tank but it containes fuel better, no slushing and steady fuel pick up, and if you add floating valves to the holes it sucks fuel from the open, under fuel, holes.
It is a pitty Keith wants his tank to be as low as possible, if you have more room below the tank you can use a gravity fed surge tank with pick up in all 4 corners, you would get fuel as long as the surge tank is below the level in the tank.

Maybe someane has an out of the box idea.:idea::)
 
brokenparts said:
Im not sure why the 4x4 community doesn't pick up on them. Every system I've ever seen seems to work great and seems like it would.be cheaper in the long run.





Sent from my DROIDX
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It requires a different shape tank, round bottom, and a system that lets the pick up run free along the bottom half of the tank. Like a ball joint.
 
Stumbled on this "A marine fuel tank includes a "sump" tank compartment. The sump tank compartment projects from and below a main fuel tank compartment. A bottom cover plate, covering the sump, has a large hole in its center in communication with one end of a connection tube. The bottom cover plate for the sump also includes two small holes directly in front of and behind the connection tube, aligned with each other in a direction of travel. These holes allow fuel to move from the main fuel tank compartment of the fuel tank into the sump tank compartment. As the main fuel tank compartment is filled with fuel, the fuel flows to the sump tank compartment by gravity feed through the holes in the cover plate of the sump tank compartment. A fuel pickup tube extends through the connection tube and into the sump tank compartment and its free end is free to move inside the sump tank compartment as moved by the dynamic acceleration forces acting on the fuel pickup tube." It only needs the sump to be round and make the most of the fuel in the sump.
 
:hhmm: my mind goes real fast, sometimes I gave to tell it to slow da fawk down.
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Mace said:
How Things Work: Flying Upside Down | Flight Today | Air & Space Magazine



BTW, surge tanks work awesome. Cruiser 88 was referencing one in his own "special" way :)

This would work well

Summit Racing SUM-300100 - Summit Racing® Aluminum Overflow Tanks - Overview - SummitRacing.com
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Travis Carpenters 4405 buggy had a circuit of fuel line that pumped from the cell up into a tank under the hood. It was a cylindrical tank taller than its own diameter, probably half a gallon or less in size. It fed to the bottom and returned from the top, with a regulator keeping it at a set pressure. There was a second fuel pump that fed from there to the fuel rails and returned to the holding tank. This was the 2010 KOH buggy that DNF'd due to pump failure, actually. The system worked really well otherwise, but it may have been too complicated.

Walbro pickups are about 25 bucks each. To do an array of 4, you need 4 of them, 4 segments of the submersible 5/16" fuel line that fits them, 2 feet of submersible half inch fuel hose (Jaz sells their pickup hose in 1 footers much cheaper than the super expensive Gates hose which meets the submersible standard) and some T fittings to connect it up. You probably put around $150 in the tank. However, then you're done. There's no welds to leak check, you can have all the fittings on top of the cell where they're not chronically exposed to hydraulic force, and you can rig the shut off valves where you can reach in an emergency.

There's a reason you don't see lots of wild pictures of innovative aerospace-ish looking fuel systems that are in use, being posted and argued about here. It's because complicated clusterific building methods yield failure in the brutal mechanical test that is 4WD. Simplicity isn't just elegance, it's a survival feature.
 
BellyDoc said:
There's a reason you don't see lots of wild pictures of innovative aerospace-ish looking fuel systems that are in use, being posted and argued about here. It's because complicated clusterific building methods yield failure in the brutal mechanical test that is 4WD. Simplicity isn't just elegance, it's a survival feature.
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Flip side to that is how sturdy those aerospace systems are. Running out of fuel or having the pickup fail during aerobatic maneuvers tends to make the news.. Running out of gas on a Rockcrawling trail doesn't ;)

Chicago, just flip for the Walboros..
 
REMOTE FILL IDEA, USING STOCK PUMP!?!?!?!?!
Okay...This is my LAST ditch attempt as trying to make this stock pump work. This is for the idea of having the PUMP mounted in the front of the tank under the trap hatch I cut in the floor and hooking a TUBE with a walbro pick up on the end running to the BACK of the TANK into a sump.

All on the same page???

So on closer inspection of where the stock pickup sock is, I noticed that it is held in by ONE plastic tab that if you close it with a pair of pliers, you can pop it off. All that is left then is a small tube.
My thought on this, is IF I were to thread this small tube and thread in a barbed 90 in to it, I can clamp a hose and run it down to the rear of the tank and drop it into a sump, so the pick up is then positioned in the rear of the tank, safely immersed in fuel.

Here are some pics.

First is of the "sock" where it goes on the pump...I had obviously removed it and am holding it in place.

2nd is another of the sock

3rd is the hole the sock attached on that I think I could thread in a 90 fitting.
005 (4).webp
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couple of the pump over all...

So the situation at this point is, if this doesnt work...I have to scrap it altogether and go with the in line...all or nothing sort of deal. I CAN NOT drop the rear of the tank any further without feeling uncomfortable. I WILL be dropping the level of the wrap bar cuz its easy to do, itll protect the DS a bit and allow a bit more safety clearance from that tank, so its worth it to cut the lower tube a bit and drop the level.
So...If any of you see ANY problems, I REALLY WANNA HEAR EM!
Dont think itll work?
connections wont be secure enough?
Too much length on the new pick up tube will be too much draw on the pump?

Remember...This route I CAN build in a pretty sizable sump too, so in theory it would be IDEAL for me.

ANYTHING that you guyz see that Im not.

Either way, Ive got a pump picked out for the in line and am fully prepared to do that if needed as well, but at least Ive exhausted ALL options.

Thanks all!
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A single Walbro pickup is a bad idea because if it sucks shut, you're vacuum locked. The whole point of those is that there are at least two, and usually more. Holley sells a kit with these things in an array, I think in sets of two. If you go with a sump, you just need a pickup tube in it, perhaps with a weighted end.

The other thing about the Walbro pickups is that they were originally made for snowmobiles. They weren't intended for 300 horsepower and the flow channels are relatively small. I think the channels in the pickups themselves are about 1/4" and the hose whips they fit are 5/16" which is a totally bastard child hose size. I just got 3/8" fittings and rammed that stuff on there.

Now, I don't know what the flow dynamics are supposed to be for most of these external pumps but it's standard to plumb from the tank to the pump in AN-8 fittings and 1/2" hose. It's AN-6 and 3/8 hose on the pressure side after the pump. In theory, the Walbros represent a flow resistor in the low pressure side which is sort of a no-no. That's why I have 2 pickups plumbed together in a T feeding half inch hose, and then two plumbed together on the other side, feeding half inch hose, and then those two half inch hoses plumbed together for the half-inch run through the pre-filter and into the pump. My fantasy is that I've eliminated (or at least minimized) the low pressure flow resistor that would make the pump work too hard.

Maybe it's inconsequential, and one 5/16" hose would feed the pump just fine... but I'm paranoid and that seemed like an avoidable problem.

Personally, I think the sump plan is a fine idea and all you really need is to have a hose in the low spot that leads to your pump. My guess is that "sock" is a decent pre-filter so you should probably figure out how to use it. If you can put the pump directly over the sump and have a straight drop of hose or tubing go the last few inches into the bottom, then you'll have the least flow resistive low pressure plumbing possible. Try not to add any spots that are narrower or more turbulent than what's already there.

Can you screw a threaded adapter straight into the plastic and feel secure about it? Maybe you could have a hose barb pointing down off of the bottom so that you could run a few inches of hose below that with the sock on the end.

What I'm curious about is the 3 hose barbs on the top. One is obviously the pump output. Is another one the return and the last one a breather?
 
I am running a man-a-fre aux tank..i think. with a pre filter, bosch pump, regulator, post filter with all stainless braided and AN fittings. As for all the walbaro picks up and everythng I am becoming worried that my set up might get a dry suck. Definatly dont want a dry suck, its always gotta be a wet suck. :lol: But I set my regulator at 59-60 psi. It work fine. I have had a minimum of 3.5 gal in the tank and it never stutter or sputtered on flat ground at least.
I would be worried about it sucking the tank into a vacuum, but my gas cap doesnt seal tight. No emission controls for me :)
FuelSys03.jpg

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FuelSys05.jpg
 
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BellyDoc said:
A single Walbro pickup is a bad idea because if it sucks shut, you're vacuum locked. The whole point of those is that there are at least two, and usually more. Holley sells a kit with these things in an array, I think in sets of two. If you go with a sump, you just need a pickup tube in it, perhaps with a weighted end.

The other thing about the Walbro pickups is that they were originally made for snowmobiles. They weren't intended for 300 horsepower and the flow channels are relatively small. I think the channels in the pickups themselves are about 1/4" and the hose whips they fit are 5/16" which is a totally bastard child hose size. I just got 3/8" fittings and rammed that stuff on there.

Now, I don't know what the flow dynamics are supposed to be for most of these external pumps but it's standard to plumb from the tank to the pump in AN-8 fittings and 1/2" hose. It's AN-6 and 3/8 hose on the pressure side after the pump. In theory, the Walbros represent a flow resistor in the low pressure side which is sort of a no-no. That's why I have 2 pickups plumbed together in a T feeding half inch hose, and then two plumbed together on the other side, feeding half inch hose, and then those two half inch hoses plumbed together for the half-inch run through the pre-filter and into the pump. My fantasy is that I've eliminated (or at least minimized) the low pressure flow resistor that would make the pump work too hard.

Maybe it's inconsequential, and one 5/16" hose would feed the pump just fine... but I'm paranoid and that seemed like an avoidable problem.

Personally, I think the sump plan is a fine idea and all you really need is to have a hose in the low spot that leads to your pump. My guess is that "sock" is a decent pre-filter so you should probably figure out how to use it. If you can put the pump directly over the sump and have a straight drop of hose or tubing go the last few inches into the bottom, then you'll have the least flow resistive low pressure plumbing possible. Try not to add any spots that are narrower or more turbulent than what's already there.

Can you screw a threaded adapter straight into the plastic and feel secure about it? Maybe you could have a hose barb pointing down off of the bottom so that you could run a few inches of hose below that with the sock on the end.

What I'm curious about is the 3 hose barbs on the top. One is obviously the pump output. Is another one the return and the last one a breather?
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Doc.
I think you eluded to a potential problem that I see with this idea. In that the ID of that plastic tube that hangs down IS 5/16. Now if I were to thread a fitting in there , that would restrict the orifice size and could conceivably cause an issue. However, there is some meat around that plastic port, so I THINK I MIGHT be able to swing it.
Re. ANY THING running below the PUMP...NO WAY. If I had the ability to do that, Id just run it in the back of the tank, leave it alone and be done. This whole plan hinges on me being able to run it on the front of the tank while having the pick up be located at the rear.
As far as anything being threaded in there and coming out? First things I thought of...So if you look at the pump, there are rubber "feet". Those are where the bottom of the tank are to be situated for stability. If I were to thread a stainless or brass 90* fitting in the bottom of it and made it flush with the bottom of those feet, it would really have no where to go. Then considering I have the tubing coming off the end of the 90 running flat along the bottom, it WONT un thread, cuz that'll be dropped down into a sump. The hose would be different in that I would NEED to run hose clamp. However...hose clamps do seem to be used without a whole lot of issue, especially if there is a barb to keep it in place.
I forgot about that aspect of the walbro. I guess that I would have to find a different way for the pre filter / sock for that. That was what I was eluding to in an earlier post re. the walbros closing shut. However, I see that if you had more of them it would help with that issue. As for the stock sock...that would be tough, cuz it slips over the end of the tube on the bottom of the pump. That would be the one item that would likely slip OFF and BONE ME!
Right now, I need to track down some fittings and see if I could match the ID with the fittings and get it all mocked up BEFORE I do any permanant damage to the pump.:hillbilly:

The ports off the top...the E plugs are power and sender, and the 3 plastic ports pickup, return and vent as you stated.
That is what makes this whole thing sort of ideal. Everything is contained ON THE PUMP. So there is really only ONE hole that NEEDS to be made in the tank and that is the pump mount. Just like you said. the least amount of welding yields less leaks to check for. Not to mention the cost savings in fittings and also the sender.

I am a bit worried about being able to match the 5/16 ID of that port off the bottom though. If I cant match that, it gonna get scrapped.
 
Why not make a plate with a tube welded on to connect to the pump. You can conect it in a similar way the sock is conected. Then connect a rubber hose to it and go from there. Like in this example. This way you can place the pump where even you want.
tank with walboros.webp
 
I also don't know anything about the stock regulator and fuel rail system on your engine. I don't think it's a flow-through system so I think that means you need to have either a fuel pump with a built in bypass/regulator to dump the excess back into the tank, or else you have to use a pump followed by a regulator that dumps the excess back to the tank (or else replace everything with a flow through fuel system...) Then the pressure regulator up at the fuel rails is just to put the pressure right where the injectors expect it.
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Chicago's engine utilizes an OEM flow-through system, so you don't need to worry about the pressure regulator (Lord knows you all are worrying enough about everything else:lol:).The only instance you need to use an in-line pressure regulator (e.g., the Corvette pump/PR combo) is on a 2004 and newer Vortec and/or LS engine AND and in-line pump.
 
I think your idea is very workable.

One option would be to use the shape of the sump to make it easier to rig that pickup hose. If the sump were wedge shaped, sloping down and back from under the pump, you could have more space to work that fit up and still have support for the rubber feet.

For the sock, how about rigging something that looks like the pool sucker from the operating room? It's a tube with lots of holes on the end of the suction hose. You could figure something like that to fit on the end of your pickup hose with minimal flow resistance, and wrap it with the sock material.
 
Ping pong balls..

outside the box :D
 
Mace said:
Ping pong balls..

outside the box :D
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Hmmm, I thought the balls where for inside the box.;)

But a pick up hole in each corner with on the inside a small bracket to keep the pingpong ball above the holes. Maybe make a cage all the way to the top so you can replace them if necesary.:hhmm: One inline pump, its cheap and functional. Does anybody know if they are fuel resistant?
 
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