Truck left me stranded today.

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Grit dog

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About 6" in front of the switching valve (under the rock guard). About as close as you can get I suppose.
That's good and yes, about as close as practical.
 

SirRobyn0

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About 6" in front of the switching valve (under the rock guard). About as close as you can get I suppose.

That's good and yes, about as close as practical.
Yes that's as close as practical, but it's actually not all that great. Electric pumps are really great at pushing fluid, but really terrible at pulling fluid.

One more thing to think about is each one of the pick up tubes in the gas tank has a sock on it, they are kind of like a prefilter screen. If those socks are 40 years old they probably don't flow great and that's just another notch in the "belt" so to speak. If the fuel filter is located before the fuel pump, that's another thing it has to pull though. The fuel filter should be after the pump so the pump doesn't have to draw though it. The socks in the tank, if in good condition should be enough to protect the pump. For that matter if your still running the Q-jet there is a filter in the inlet of the carb, and you could just run that and eliminate the inline filter all together.
 

Grit dog

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@SirRobyn0
I totally agree. The fact that any aftermarket pump still has to pull at a minimum the water column height of an empty fuel tank is not ideal.
Although anything to reduce that and other minor losses helps.
 

sgrinavi

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Yes that's as close as practical, but it's actually not all that great. Electric pumps are really great at pushing fluid, but really terrible at pulling fluid.

One more thing to think about is each one of the pick up tubes in the gas tank has a sock on it, they are kind of like a prefilter screen. If those socks are 40 years old they probably don't flow great and that's just another notch in the "belt" so to speak. If the fuel filter is located before the fuel pump, that's another thing it has to pull though. The fuel filter should be after the pump so the pump doesn't have to draw though it. The socks in the tank, if in good condition should be enough to protect the pump. For that matter if your still running the Q-jet there is a filter in the inlet of the carb, and you could just run that and eliminate the inline filter all together.


Both pick ups / sending units were changed this summer and the tanks were flushed while I had them out. I have two filters, one in the engine bay and the one on the carb that was changed after the tanks were flushed - about 1000 miles ago. I'll take a look at that if I have another incident.
 

SirRobyn0

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Both pick ups / sending units were changed this summer and the tanks were flushed while I had them out. I have two filters, one in the engine bay and the one on the carb that was changed after the tanks were flushed - about 1000 miles ago. I'll take a look at that if I have another incident.
If the tanks are clean. As in not rusty, in my experience you can flush a rusty tank, but the rust comes back. So as long as they weren't rusty I'm sure those socks are just fine then. Sounds like you have a decent fuel system, I'd just keep in mind the electric pump thing...
 

AuroraGirl

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Yes, the coolant temp. It was about 180 today, it's been as high as 210 when one of my fans crapped out.

In line fuel filter looks suspect too, so I swapped that out.
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I will change the coil, cap and module. Can't hurt. THANKS!
Those filters are not high quality, get yourself a metal wix (Im sad wix is selling that kind..)
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This product people have said is decent when using both SBC and electric pump, as it will allow flow-through when off. which means you could have it on a toggle at the very least to check the theory about vapor lock concerns.All fuel hose clamps should be replaced with fuel injection clamps if you have cheap worm ones them up by the fuel pump, air can sneak by and then throw wrench into your issue.

as to the question of where to place an electric frame pump, if you had one tank I would say below the level of fuel if all possibly and a model without a check valve as close to the tank.
If you have 2 tanks, a check valve pump can be placed further away and below fuel level if possible, but im not sure how it would interact with tank switching valve. I believe ford in the late 80s used the same one as the late 80s GM, but they had their pump before but I could be mistaken
 

SirRobyn0

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Those filters are not high quality, get yourself a metal wix (Im sad wix is selling that kind..)
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This product people have said is decent when using both SBC and electric pump, as it will allow flow-through when off. which means you could have it on a toggle at the very least to check the theory about vapor lock concerns.All fuel hose clamps should be replaced with fuel injection clamps if you have cheap worm ones them up by the fuel pump, air can sneak by and then throw wrench into your issue.

as to the question of where to place an electric frame pump, if you had one tank I would say below the level of fuel if all possibly and a model without a check valve as close to the tank.
If you have 2 tanks, a check valve pump can be placed further away and below fuel level if possible, but im not sure how it would interact with tank switching valve. I believe ford in the late 80s used the same one as the late 80s GM, but they had their pump before but I could be mistaken
So if I understand correctly you are saying injected vehicles have the pump before the tank valve and yes that is correct, as those pumps were in the tank. It actually would probably be better for a guy on a carbureted rig to have two pumps one as close as humanly possible to each tank, and install a tank valve that can handle the pressure and either the power for the pumps or set up a relay to run them. But most guys don't wanna run two pumps and go though all the extra work, for what in reality is only a marginally better set up.

I don't think a check valve matters to the tank valve at all.

Like I said early on, I'd be doing everything possible to go back to a mechanical pump BC they are far more reliable than any electric pump mounted to the frame rail will be. It's simple and back to factory. But we should not forget he's not trying to rework his fuel system per-say he has a an issue to solve, which may or may not be fuel related.
 

AuroraGirl

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So if I understand correctly you are saying injected vehicles have the pump before the tank valve and yes that is correct, as those pumps were in the tank. It actually would probably be better for a guy on a carbureted rig to have two pumps one as close as humanly possible to each tank, and install a tank valve that can handle the pressure and either the power for the pumps or set up a relay to run them. But most guys don't wanna run two pumps and go though all the extra work, for what in reality is only a marginally better set up.

I don't think a check valve matters to the tank valve at all.

Like I said early on, I'd be doing everything possible to go back to a mechanical pump BC they are far more reliable than any electric pump mounted to the frame rail will be. It's simple and back to factory. But we should not forget he's not trying to rework his fuel system per-say he has a an issue to solve, which may or may not be fuel related.
Im talking about using a pump in addition to the mechanical fuel pump. a solenoid type fuel pump with a check valve wouldnt take so kindly to to the mechanical fuel pump trying to move gas while its turned off. The check valve kind allow the pumps to be mounted furhter since they dont lose prime I would assume

The pumps im talking about existed both in the tanks and outside. Ford used pushers and a mechanical, and then lift pumps in each tank that went to 1 high pressure pump (those fuel tank switching setups on that last one were ass)
I am saying to use a mechanical pump as well. If there was concern about just that pump, thats where an electric can help keep it from vapor since the line wouldnt be under harsh vacuum
 

cjdock

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Do you have a return line for the setup? If not I'd add one. My 85 c10 has an in tank pump and a pressure regulator in the engine compartment with gauge, and a return line. Q-jet carb. Starts instantly every time.
 

sgrinavi

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If the tanks are clean. As in not rusty, in my experience you can flush a rusty tank, but the rust comes back. So as long as they weren't rusty I'm sure those socks are just fine then. Sounds like you have a decent fuel system, I'd just keep in mind the electric pump thing...

I was prepared to replace them, but they were shiny inside and rock solid outside. Truck spent it's life in mountains of Nevada, not too much rust on her.

Those filters are not high quality, get yourself a metal wix (Im sad wix is selling that kind..)

I'm surprised to hear that, VGG guy recommends them and he's usually pretty solid on filters.

This product people have said is decent when using both SBC and electric pump, as it will allow flow-through when off. which means you could have it on a toggle at the very least to check the theory about vapor lock concerns.All fuel hose clamps should be replaced with fuel injection clamps if you have cheap worm ones them up by the fuel pump, air can sneak by and then throw wrench into your issue.

I like that mounting system on that pump, if nothing else. That would be an easy fix. I'm hesitant to go back to the mechanical pump, I have no idea why the guy swapped it out.

Pump is mounted right at the level of the bottom of the tank, it basically sits on the switching valve rock guard.
 

AuroraGirl

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I was prepared to replace them, but they were shiny inside and rock solid outside. Truck spent it's life in mountains of Nevada, not too much rust on her.



I'm surprised to hear that, VGG guy recommends them and he's usually pretty solid on filters.



I like that mounting system on that pump, if nothing else. That would be an easy fix. I'm hesitant to go back to the mechanical pump, I have no idea why the guy swapped it out.

Pump is mounted right at the level of the bottom of the tank, it basically sits on the switching valve rock guard.
I wonder if its a check valve kind. Also, the filter I mentioned, the filter made of plastic is the concern, not the filter media. The plastic bodies are not.. in my experience.. very reliable but wix makes a metal kind
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You can see mine here

also why do you have 2 fuel filters in line? Try removing one
 

SirRobyn0

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As far as the filter type is concerned IMO I think either the plastic or metal is fine. In the older days the plastic ones would sometimes have issues, but I think today there isn't much difference. I'm running a metal one on mine BC it's what I'm use to using, but I see plenty of the plastic ones out there working just fine.
 

sgrinavi

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Do you have a return line for the setup? If not I'd add one. My 85 c10 has an in tank pump and a pressure regulator in the engine compartment with gauge, and a return line. Q-jet carb. Starts instantly every time.

Well... I have the return lines, but now that you mention it I have not chased it past where it hooks up to the switching valve. I need to figure that out.
 

sgrinavi

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also why do you have 2 fuel filters in line

I have one that I can see, which I prefer, and the one in the carb. I would take the one out of the carb if there was any question. Why would having a second filter be an issue?
 

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