EFI In Tank Pump Baloney

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matthon

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Riddle me this in-tank pump manufacturers and vendors -

For an EFI conversion, it is recommended to use the best of the best for the fuel system, for performance, longevity, and safety.
Depending on the company, or the consumer's opinion, there are many factors and requirements.
For example, and I'm not being too specific here, the type of fuel line, fittings, pump, o-rings/seals, routing of lines, etc.

In my case, AN fittings, braided stainless teflon fuel line, 90 gph/340 lph pump, filter, regulator, wiring, etc.

So why with the in-tank pumps do the manufacturers, Holley, Hyperfuel, Aeromotive, TanksInc, and others, I'm talking to you, use a rubber efi hose from the pump to the underside of the housing, with either a clamp and a clamp, a clamp and a barbed/press/push-lock fitting, or a nylon hose with a clamp?

In the most inaccessible place in the entire system, with the highest fuel pressure in the system, before the regulator, in what universe does it make sense to run a hose with clamps?

Use our super fantastic braided hose, our ridiculously priced fittings, and our tools to put it all together, don't skimp here, no, you'll regret it, your safety depends on it.

Oh, the in-tank pump? Here, we've supplied you with this sate of the art aluminum housing, machined by high tech computer controlled equipment for accuracy, AN fittings for a leak proof union, and a ridiculous pump that has so much psi you'll never need and will explode even your existing fuel line if you use it as a return.

And here's a Fisher Price fuel line and clamps, or not, to connect our super pump to our super housing.

I've been dealing with this issue, unbeknownst to me, since day one.

The upper end of my hose has a barbed/push-on fitting where the hose slides on, and you cannot pull it off, with a clamp on the bottom. A clamp will not fit at the top, and a clamp on that fitting doesn't seem correct to me.

Hoses expand, get soft, burst.
Clamps fail, ruin hoses.

In my case, the barbed fitting comes to a point, the hose goes over it which leaves a space between the opening and the hose. Hose gets soft, expands. I've removed it enough times to tell you the short length of hose is much softer than the original hose.

Add 100+psi, how long before it pushes past the barbs?

Answer: 20 minutes from 58psi at the throttle bodies to 40psi, another 10 minutes gets you 24psi.

In my case, the manufacturer has been very helpful, and is sending me a different, longer upper fitting, different clamps, and new hose, however I'm going to see if I can locate my own fitting just to compare.

Still weary about clamps on both ends.

Just an FYI to those who may be experiencing fuel pressure issues, or an unknown issue.
In my case, me and my ecu were compensating for an AFR that was too lean, and they replaced the pump twice. I had a pressure gauge which was giving me a bad reading, also it was not liquid filled. I had ordered the wrong one and it took a while for the other one to arrive, and for me to get off my butt to install it.

It wasn't until I loosely set the housing/pump in the tank that I noticed the issue, as gas sprayed out horizontally between the housing and the tank.

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Wondering if the factory setup is similar, different or what? Since the factory setup HAS TO BE reliable for a long time/100,000 or more miles, why wouldn’t the aftermarket copy the factory setup?
 
Most every in tank pump assembly I have ever pulled apart, and that's been QUITE a few, use rubber hose directly off pump. Some newer units have plastic "channels" or assemblies, that mate directly to the pump with large, or thick, rubber grommets. Vibration/harmonics, I'm guessing, play a major role in no hard connections.
 
Vibration/harmonics, I'm guessing, play a major role in no hard connections.

In all the examples above, the pump is secured to the housing, which is bolted to the tank. Only the first one has a thin piece of gasket material around the pump.
 
In all the examples above, the pump is secured to the housing, which is bolted to the tank. Only the first one has a thin piece of gasket material around the pump.

The drop in module style are almost all built using that method. Only a select few rubber fuel lines are submersible, and the ones that go in the tank, must be of that type. Regular fuel line won't last a week submersed in fuel. The submersible hose is expensive, especially in the larger diameters. I also prefer the marine-grade hose clamps.

I used a pair of Holley Hydramats fed by 10AN barbed common brass fittings to an externally mounted pump. On my set-up, they only see suction not pressure. All the pressure side is Earls stainless line and fittings.

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The drop in module style are almost all built using that method. Only a select few rubber fuel lines are submersible, and the ones that go in the tank, must be of that type. Regular fuel line won't last a week submersed in fuel. The submersible hose is expensive, especially in the larger diameters. I also prefer the marine-grade hose clamps.

I used a pair of Holley Hydramats fed by 10AN barbed common brass fittings to an externally mounted pump. On my set-up, they only see suction not pressure. All the pressure side is Earls stainless line and fittings.

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I have always wondered "not to jack the thread" , but are u guys cutting holes in the trunk floor to have access to the in tank pumps / Or dropping the tank everytime something goes wrong ?
Seems to me that an inline pump behind the tank would be easier for service or replacement -----And I cant hear , mine once the engine is started ------
 
The hose s/b submersible, but then again not sure how to tell.
I've used nothing but the hose that came with it, it was a long piece.

No hole in floor.
An inline pump would be easier, if you had to drop the tank 5 times to figure out a major design flaw.

The tank has a lowered flat area, it all fits nicely. It's not bad to drop when empty or very low. Wouldn't be a bother if I had to drop it when a new pump went, which s/b a while, hopefully.

I'm thinking they all skimp on the pump/housing connection because it's cheaper, and it's ok if it fails in a closed tank, no or less liability.

I'm not driving it, but I checked and it's down to 5-10psi. Probably blew the hose right off or destroyed it.
 
Any recommendations on the best parts to use to get from the fuel pump to a tbd fitting, I'm all ears.

Specific hose, clamps, fittings, whatever.

Need to make it stick this time.
 
I have always wondered "not to jack the thread" , but are u guys cutting holes in the trunk floor to have access to the in tank pumps / Or dropping the tank everytime something goes wrong ?
Seems to me that an inline pump behind the tank would be easier for service or replacement -----And I cant hear , mine once the engine is started ------
Good idea. Didn’t work out due to trunk floor configuration in B Body. Dropping a tank on the road no fun. Got a PWM pump in the Rick’s Tanks reported to be long life due to at rest design.
 
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This is what was sent to me, so I cut that sob open.

I thought a barb fitting and a clamp don't mix?

Wouldn't a fitting meant for a clamp be better?

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This is what was sent to me, so I cut that sob open.

I thought a barb fitting and a clamp don't mix?

Wouldn't a fitting meant for a clamp be better?

View attachment 1715317767
I aint no expert on the intank stuff , but my fast 2.0 / external pump set up came w/ pushlok fittings and almost that exact same clamp. I have had no trouble out of it for quite a few yrs. now. I have had occasion to change things w/ three diff. intakes, and have found nothing that is deteriorating .
I`m wondering if u got the wrong hose sent in ur kit to start with !! I have checked those brass barbed fittings and found them to be the same size as the pushlok barbs too------
I have used a heck of a bunch of those brass fittings over the yrs. , nothing wrong w/ them , just cheaper . Even used a few in plumbing over a 50ish yr career .
 
What's to stop you from making all new lines from teflon-lined hose? Use all AN/aircraft style fittings and adapters.
 
Many of the factory replacement pumps have no barb of any sort on the pump outlet. Its dependant on the bracket/mount to hold pump inline with the fuel line going out of the tank.
I know some pumps will build pressure to 175 psi.
So a hose failure is not uncommon, but mis-matching hose and clamps is a failure waiting to happen.
The efi approved hose is very expensive compared to regular hose and needs the proper clamp to seal.
Having pump in tank is still the best,as far as pump losing prime goes. Plus its easier to push fuel than to pull it. Also prevents vapour lock.

I have not done anything with high performance fuel pumps, but have replaced hundreds of in tank factory pumps. They are all junk.
 
Many of the factory replacement pumps have no barb of any sort on the pump outlet. Its dependant on the bracket/mount to hold pump inline with the fuel line going out of the tank.
I know some pumps will build pressure to 175 psi.
So a hose failure is not uncommon, but mis-matching hose and clamps is a failure waiting to happen.
The efi approved hose is very expensive compared to regular hose and needs the proper clamp to seal.
Having pump in tank is still the best,as far as pump losing prime goes. Plus its easier to push fuel than to pull it. Also prevents vapour lock.

I have not done anything with high performance fuel pumps, but have replaced hundreds of in tank factory pumps. They are all junk.

The way I have dual pick ups coming out the back lower corners of my tank, they will feed the external pump mounted close to the frame ahead of the rear bumper just about by gravity, so no problem there.
You are correct in that the special fuel inj. hose is expensive, I looked it up on the fast website and it was crazy ! I bought a pushlok union and spliced it on my last intake swap, lucky I had some extra !
 
Just out of curiosity why does no one use the universal sump kit from edelbrock? It seems so much simpler. No return line or in tank fuel pump. Easy access and keeps your mechanical pump.
 
Many EFI systems require a return line.
Correct me if I'm wrong, but the only reason they require a return line is because they're using an in tank pump.. the edelbrock sump is a universal kit that is advertised for use with all efi systems..
 
Correct me if I'm wrong, but the only reason they require a return line is because they're using an in tank pump.. the edelbrock sump is a universal kit that is advertised for use with all efi systems..
If you look at FiTech, for example, the regulator is inside the body of the unit. The fuel line goes in one end of it, and out the other end. That fuel coming out has to go back to the tank. That is how they say to hook it up. Maybe you can do it differently, I don't know.
 
Correct me if I'm wrong, but the only reason they require a return line is because they're using an in tank pump.. the edelbrock sump is a universal kit that is advertised for use with all efi systems..

OK, my external pump has a return line too .
 
What's to stop you from making all new lines from teflon-lined hose? Use all AN/aircraft style fittings and adapters.

All my lines are braided covered teflon with AN fittings.
The fuel pump will only accept a rubber hose/clamp.

The Edelbrock sump is an add on to your existing pump mounted somewhere in the engine compartment. No thank you, not for me.

I have thread tape for gasoline. The white thread tape sent to me is incorrect.

I passed on the tanksinc pump because it had npt fittings, and drilled a giant hole in their tank to fit this super fast aluminum AN fitting unit. Now I need to make it work.

The clamp is good, I'll need another for the pump side.

I'm going to look for a better fitting.

Not sure how to tell if the hose I have is FI hose?
 
All my lines are braided covered teflon with AN fittings.
The fuel pump will only accept a rubber hose/clamp.

The Edelbrock sump is an add on to your existing pump mounted somewhere in the engine compartment. No thank you, not for me.

I have thread tape for gasoline. The white thread tape sent to me is incorrect.

I passed on the tanksinc pump because it had npt fittings, and drilled a giant hole in their tank to fit this super fast aluminum AN fitting unit. Now I need to make it work.

The clamp is good, I'll need another for the pump side.

I'm going to look for a better fitting.

Not sure how to tell if the hose I have is FI hose?

Why not order some from summit, plainly says fuel inj. , nhra approved too ! F.A.S.T. fuel inj has it too/owned by compcams --------
 
All my lines are braided covered teflon with AN fittings.
The fuel pump will only accept a rubber hose/clamp.

The Edelbrock sump is an add on to your existing pump mounted somewhere in the engine compartment. No thank you, not for me.

I have thread tape for gasoline. The white thread tape sent to me is incorrect.

I passed on the tanksinc pump because it had npt fittings, and drilled a giant hole in their tank to fit this super fast aluminum AN fitting unit. Now I need to make it work.

The clamp is good, I'll need another for the pump side.

I'm going to look for a better fitting.

Not sure how to tell if the hose I have is FI hose?
u cant use a -06 ptfe hose in there ?
 
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