The Oh Fishall Fuel Pump Thread

[farmersammm]

This system (see!! Beer Nite is the Thinkers Corner!! Twas time well spent!) is totally different from what us old timers are used to.

The old single hose systems depended on gravity to fill the tank. The new 2 hose system is totally different.

The inner hose functions as an extension of the pump nozzle, and the only function the outer hose serves is to shield the inner hose.

So..............all's I gots to do is replace the small inner hose,, and put together something with my new flex hose to bridge the gap between the metal outer filler neck, and the outer hose that's left.

Because I didn't think this through, I modified the original filler neck by cutting off the inner hose nipple. I need to either weld that back on, or take a filler neck out of the parts truck to replace it.

The takeaway, if I'm correct................these systems are pressure fill, not gravity fill (the light goes on)

This has to be correct. If you look at the original intact hose assembly on the front tank, it actually dips BELOW the tank on its way to the tank. THIS IS A PRESSURE SYSTEM!!!!!!!!!!!!!!!!!!!!!!!!

[Oxford1]

This system (see!! Beer Nite is the Thinkers Corner!! Twas time well spent!) is totally different from what us old timers are used to.

The old single hose systems depended on gravity to fill the tank. The new 2 hose system is totally different.

The inner hose functions as an extension of the pump nozzle, and the only function the outer hose serves is to shield the inner hose.

So..............all's I gots to do is replace the small inner hose,, and put together something with my new flex hose to bridge the gap between the metal outer filler neck, and the outer hose that's left.

Because I didn't think this through, I modified the original filler neck by cutting off the inner hose nipple. I need to either weld that back on, or take a filler neck out of the parts truck to replace it.

The takeaway, if I'm correct................these systems are pressure fill, not gravity fill (the light goes on)

This has to be correct. If you look at the original intact hose assembly on the front tank, it actually dips BELOW the tank on its way to the tank. THIS IS A PRESSURE SYSTEM!!!!!!!!!!!!!!!!!!!!!!!!

It's not a pressure system. At no point should any portion of the tank or filler neck be under pressure. At all- unless you removed the vent from it. You cobbled up a mess, and now the filler neck fills up with gas because it can't flow into the tank faster than it's being pumped in, and the Venturi effect shuts off the pump nozzle. Get rid of your self-inflicted restriction and it will fill just fine. If the fill line goes below the tank, then it was previously cobbled and it's created a trap, which serves to further restrict flow. Throw away all your mess, get an upfitters kit from Transfer Flow, and fix the damn thing right.

[farmersammm]

It's not a pressure system. At no point should any portion of the tank or filler neck be under pressure. At all- unless you removed the vent from it. You cobbled up a mess, and now the filler neck fills up with gas because it can't flow into the tank faster than it's being pumped in, and the Venturi effect shuts off the pump nozzle. Get rid of your self-inflicted restriction and it will fill just fine. If the fill line goes below the tank, then it was previously cobbled and it's created a trap, which serves to further restrict flow. Throw away all your mess, get an upfitters kit from Transfer Flow, and fix the damn thing right.

This is a public forum, so I guess folks such as yourself are the cost of using a public forum (shrug)

The original FACTORY, or upfitter/body builder hose assembly, which has worked fine for all of the time the truck has been in my possession, is as shown...... This is the undamaged front tank hose.

Takes gas at the full open setting on any fuel pump. It really doesn't look as if it's a totally downhill run to the tank, does it boss??

The interior of the assembly carries another smaller hose, which begins where the fuel pump nozzle ends, as it's inserted into the filler neck through THE SEALED FLAP DOOR ASSEMBLY COMMON ON MODERN VEHICLES.

This is a 1" ID hose that goes all the way to the tank. ONE INCH..........kinda restricted woudn't ya say?
And, I'd venture a guess that there ain't any air that escapes back up this hose to vent the tank as it's being filled. We on the same page?

I'm sure just about everyone on the planet has had a fuel pump fail to shut off. It doesn't drizzle out on the ground. It's under pressure. They don't have the old gravity fill pumps these days Edison figured a way around that

If you still wish to persist with the "no pressure" thing..........I'll give ya atmospheric pressure as maybe the maximum pressure(14psi). But if you think about it.......that gas ain't gettin' up out of that underground tank, and in your tank unless it's under pressure. Unless you want do a great Tik Tok video showin' us how ya wrap your lips around the nozzle, and suck.

At first, I thought that the gas was getting backed up in the cobbled together neck.

The neck, sch80 pipe, and 2" big outer filler hose fitted to the pipe, are above the tank filler neck. Gravity oughta work......yeah? It ought to take gas if it's run slow. As a matter of fact, the gas will flow for a few seconds, and then it shuts off. Air ain't gettin' out. It's like the new unvented gas cans.

Gravity works allright,, but there's nowhere for the air to go. This assembly is welded to the original unleaded flap filler neck. AND MOST IMPORTANTLY.......THE AIR HAD NOWHERE TO GO WHEN THE ORIGINAL ASSEMBLY WAS INTACT. It all goes through the EVAP cannister. Gas goes in ,till the tank is full, and the flow meets resistance from the liquid that's now at the full level. When the gas backs up in the 'new' neck, it's shutting the pump down. If the neck was an old fashioned full 2" diameter neck, without the sealing flap, it would fill.

12v71 is probably spot on about drilling holes above the flap. I'd rather have it as close to original as possible,, and get it back to working through the EVAP system like it's supposed to.

So..................I have to get around to testing the EVAP system to see if it's burping air. And, I'll also weld the nipple back on the original filler neck (which simply mates to the new neck with nitrile hose) and get some PVC hose to fit the nipple, and run it down to the tank filler inlet inside the big hose. It should fit through the opening in the 'new' neck gizmo.

https://www.gilsoneng.com/reference/ChemRes.pdf PVC holds up well to gasoline, and ethyl alcohol, according to the info. So I ought to be good.

I assume all vehicles use the same system https://www.partsgeek.com/m1hh6pt-fo...Ad+group+%231& Look under any of the older trucks, and while some have a good slope to the tank, others are either flat,, or have a slight droop somewhere along the way. They simply let the pump push the gas till it backs up at the bottom of the small inner hose. The hose could go uphill, like mine, and it still works fine. My 'new' neck might not be letting the gas "turn the corner" fast enough,, but at a low flow rate it shouldn't matter. My old PowerWagon has the old style regular gas single 2" hose, and it takes a dribble to get fuel in it......big hose, pretty steep slope........air problems. Nothing was vented back then, just the gas cap.

[farmersammm]

Leaving the original filler neck as intact as possible, I ran the hose at the same angle as the original hose was at one time. The large outer hose is a solid molded assembly.........it's not flexible, and won't attach to the inlet on the rear tank in any other angle than what I have it at. This is the way it was from the factory. All of the original hoses are hard molded rubber/plastic. They were custom made for the application. They do NOT bend until they're close to the clamp. I dunno how they made them like that................hard about 80% of the length, and soft at the clamping areas. I guess Ford has a better idea All kidding aside, when you plunk your money down for a vehicle, you're paying for an incredible amount of engineering, and foresight. They are engineering marvels...........we forget this sometimes.

This is apparently common on these Fords built during these years. The little F-150 has the identical arrangement on the rear tank.

The hose is flat going into the tank. No downhill angle.

The hose enters the tank at the same angle as on the F-350......no real inclination. It's the way they built them.

Now......the front tank is identical too. The hose climbs on the way to the tank.

At the risk of repeating myself............it's the way they built them. (If you look carefully at this picture, you can see how the hose on the back tank climbs over the frame too)

Anyways..........................don't be laughin' at my welds. I am not a pipe guy. I was doing good, IMHO, just to get this damn thing to stick together

[farmersammm]

To give a truer picture, let me straighten the previous one up a bit to represent true vertical alignment of the tire, and suspension, in relation to the fuel filler hose.

None of these guys flow downhill. The pump has to push the gas into the tank. It's the way they built them.

[farmersammm]

If you're gonna buy a used truck, it's best to find one from the Southern, or Southwestern (Oklahoma is considered Southwest), states. Look at the underside of that pickup 27yrs on the road, and it's near pristine. We don't have to use salt here.

The F-350 originally came from Jersey, via North Carolina, via Texas. The time it spent up North was the source of the rust underneath. I'm thinking it didn't spend too much time there. It was originally a Waste Management truck IIRC..........all the old registrations were still in the glove box when I got ahold of it back in 2008.

[farmersammm]

Used them on other models of the same year. Ford just made 'em this way. https://www.ebay.com/itm/37092441060...Cclp%3A2334524

I will say that these trucks are the best "fuelers" I've ever owned. The only other tanks that ever took gas good on the older trucks were the behind-the-seat tanks where the neck was just a few inches from the tank inlet. The rear tanks always sucked.

[farmersammm]

It ain't a Jeep, or whatever you're driving https://www.ebay.com/itm/26510265257...Cclp%3A2047675 Or a Chevy, or a Rice Burner, or......................................

It's a 1994 F-350 XL cab and chassis (not a dually with the wideazz rear wheel track) which goes on the train with the hoses zip tied to the frame already there for the body builders to use. Are we clear on this?????????

[farmersammm]

IMHO, of course

[Oxford1]

Again, it’s not under pressure. It doesn’t need pressure to fill. It needs flow, which is created by the pressure drop from pump discharge pressure to atmospheric pressure that’s created when you squeeze the handle. One of two things is happening: your tank vent doesn’t work so there’s no place for the gasoline to go, or your filler neck has such poor flow characteristics that it creates turbulent flow at the nozzle outlet and triggers the automatic shutdown. Either way, it’s not pressurized. In fact, the presence of a vent that has to be functional proves that.

[cwby]

Gravity will actually push fluid uphill when conditions are right. Siphon a cattle trough with a hose, sink traps, toilets, etc. The weight of the fluid above the low point pushes it across the level or slightly uphill hose into the tank in this example.

Looks like a venting problem to me. Stick a 3/8 poly airline in the main hose just into the top of the tank & then try to fill it with the nozzle - I'll bet it will fill then.

[M J D]

We can't have solutions or else this phuckery will come to an end.

[Oxford1]

Siphons are really cool- the physics are really interesting. It boggles my mind that science can explain so much but that there is still disagreement on what makes them work. The world is a cool place. I certainly agree with your diagnosis.

[farmersammm]

I was typin' away, and got timed out. It takes gas now, the valve is bad, or a line is bad.

[farmersammm]

Neither is bad. The system simply won't function without two hoses.

The tank vent valve is not designed to vent air in volume. It's only effective in keeping pressure in equilibrium.



I have no problem filling the tank if the vent valve is removed. It's a red herring. The tank will not fill properly without the double hose configuration.

I can replace the inner hose with this https://www.fillernecksupply.com/uni...stic-flexible/ but I'm not sure I trust it. Might work, might not. The corrugation might hinder flow. Plan is to find some rigid irrigation tubing, and bend it to fit the outer hose.........like the OEM design.

The back tank opens up new horizons I love it, and have been running it regular since I installed the new pump. I get another 20 gallons of fuel. THAT'S ABOUT ANOTHER 100-120 MILE RANGE Almost 140 if I'm running empty

Yeah, the thread continues. Sorry dooooods

[farmersammm]

Ordered the parts from the outfit in the previous post today. I tried everything I could to find an alternative, but I'm at the point where I feel it's a waste of time. I NEED AN OPERABLE VEHICLE. Stupid to waste time on alternative fixes. Should get the stuff by mid week I'm thinking.

[Oxford1]

Ordered the parts from the outfit in the previous post today. I tried everything I could to find an alternative, but I'm at the point where I feel it's a waste of time. I NEED AN OPERABLE VEHICLE. Stupid to waste time on alternative fixes. Should get the stuff by mid week I'm thinking.

If only that had been suggested to you a week ago.

[farmersammm]

If only that had been suggested to you a week ago.

I'm thinkin' the fella that suggested the ultimate fix, didn't know his butt from a hole in the ground Upfitter hoses, and other blather

The outer casing/hose is the vent, the inner hose is the filler. Like original. Still have to keep the welded outer thingy. No hose available for it. Wish in one hand, and crap in the other..........guess which one'll fill up first Outer hose simply doesn't exist anymore.



Anyways, there's no other method to fix this thing. Luckily the flex hose is available. I couldn't find any thin wall pvc to fill the bill. Biggest diameter I could find was 3/4.

[Oxford1]

I'm thinkin' the fella that suggested the ultimate fix, didn't know his butt from a hole in the ground Upfitter hoses, and other blather

The outer casing/hose is the vent, the inner hose is the filler. Like original. Still have to keep the welded outer thingy. No hose available for it. Wish in one hand, and crap in the other..........guess which one'll fill up first Outer hose simply doesn't exist anymore.



Anyways, there's no other method to fix this thing. Luckily the flex hose is available. I couldn't find any thin wall pvc to fill the bill. Biggest diameter I could find was 3/4.

Actually, he did. He suggested an upfitter kit, which is actually what it's called because it's used by truck upfitters to connect factory tanks to aftermarket bodies, from a company called Transfer Flow, which actually exists and has a good business and good products which he has installed probably a hundred of. It wasn't blather, it was actual experience. You could have called Transfer Flow and told them what you had going on, and they would have either had something that would work or known where you could go. Instead, and as usual, you documented five pages of a cobbled mess, sprinkled in your usual mix of alcohol-influenced troubleshooting and mentions of your desperate need for a solution because your cows are hungry, got sore when I called you on it, and still don't have your truck fixed. I hope those cows get full when they can.

[farmersammm]

https://www.transferflow.com/shop/filler-neck-kits

Yeah..............well

I guess this would be the 101st time

[farmersammm]

https://www.transferflow.com/shop/re...ent-fuel-tanks

They're batting 1000

[farmersammm]

I know the beer thing is an easy hit, but ya gotta really get something better.

Old truck, unavailable parts, etc........................... I guess you do the best you can do.

I suppose the EGR repair was a mess too. Another unobtainable part...........one heck of a bender build (didn't share it),, and a useable part when it was all over. I'm making some dies for some hydraulic repairs on the Allis as we speak.

If everyone did things the "normal" way, there wouldn't be a WeldingWeb.

Innovations, steps backwards, steps ahead.....................the thrill of victory, the agony of defeat. Life is a continuum. It's the peaks, and valleys, along the way, that make it interesting. I think unhappy people probably haven't lived a full life............peaks and valleys......... If it's all easy, no challenges, just buying off the shelf, towing the line.........it's a boring life.

K'kins can't stand it when nothing's goin' on. I mean.......she really does NOT like it. She has to listen to me talk politics, or the market. When there's a disaster goin' on out in the shop, she has the chance to participate. I run everything by her, every step along the way. She has a STAKE. And, I listen to her. Been times when she completely turns me around, and I go the other way. We usually have a pretty good time at anything we do. (Her bee thing was the latest thing to work on.......it's been fun) (She didn't trust the hive stand until I actually attached the bungee cord that was part of the design.........Ahaa!!)

Happy.............spell it You can do theeeeeeeees

[farmersammm]

Take it a step further.......................

I give Moto crap. I do it pretty regular.

I LIKE MOTO. Moto does things a little different than the rest of us (so does Wild Bill, I LIKE HIM TOO). I would not like the world if Moto didn't exist, same with Bill. These guys are sincere, and they make you SMILE. You can't ask for better than that.

[12V71]

Just sayin' here. I have done a ton of flatbeds on trucks and have had the best filler luck by making sure the fill hos is in a straight line to the tank and drilling the fill neck just above the flap with as large of a hole as possible to vent the air out. Even with the smaller inner hose. Most diesel pickups don't do the co-axial hose thing but have an open filler neck without the flap and small hole and those will fill just fine.

[farmersammm]

Just sayin' here. I have done a ton of flatbeds on trucks and have had the best filler luck by making sure the fill hos is in a straight line to the tank and drilling the fill neck just above the flap with as large of a hole as possible to vent the air out. Even with the smaller inner hose. Most diesel pickups don't do the co-axial hose thing but have an open filler neck without the flap and small hole and those will fill just fine.

I've never questioned your veracity. Never. We've gone head to head about certain design things, but that's a matter of when stuff was made, and how it's changed over time.

You, at least, have seen the inner hose thing. It's not a fairy tale. It exists.

The whole problem is that the tank has one inlet. Period. No allowance for any other kind of venting. The air has to get out of the outside hose.

In other words, we're on the same page.

I agree that a healthy sloped single hose might do the job. It would have enough air space above the liquid to vent the air..................

I'm facing something that can't be changed without a lot of bucks to remake the entire system. The hose I bought is a solution to the problem, WHICH SEEMS TO BE A COMMON PROBLEM WITH THESE SYSTEMS..............THE COAXIAL HOSE AS YOU SAY. I bit the bullet, and got the right solution coming in. I can't see how I can do much better, and I ain't gonna take crap about it. (not your crap.........you haven't given any crap).

I came full circle, admitted my mistakes, and am going for the best aftermarket solution out there. THIS IS AN OLD F'N TRUCK, AND THERE AIN'T A LOT OUT THERE TO FIX IT.

You're right, you're golden...............but I'm looking at a low profile bed mount based on the hose configuration at the time the truck was built. My bed, and others I've seen in this year, is about 6" above the top of the frame rail. The tank inlet is exactly at the top of the frame. Is what it is. They made them this way. And they worked........with the right hose. I have the right hose coming in.

The trucks at this time(94), didn't have high profiles. This was before the push to raise the trucks to satisfy the doooooods with small hands. I think it's crap to have to climb into a 1 ton these days. Short dooods with stools

I think I'm good. I'm sticking with OEM. I like to do things as close as possible to how they came out of the factory. Otherwise you have a mess. No resale value, no real working value.

I tried to do with what I had to work with, and now I caved in to what is right.