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2 questions

Jake_C_

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First, is this my fuel pressure regulator? 3CBA3508-89FD-4536-98C3-61FD1B07D925.jpeg I assume it is it just looks odd to me. I have an in tank electric fuel pump and a carbureted motor (all done by the previous owner) this is in the middle of my main fuel line so I really just want confirmation because I can’t imagine it being anything else. I’m redoing the fuel lines but I can’t use a mechanical pump on the block so I’ll have to use a regulator again, isn’t somewhere around 7psi ideal for carburetors?

Second question, where do your vapor lines end for your fuel tank. The small 1/4 one that runs all the way to the front. Mine seemed jerry rigged so I wanted to see what’s normal. Thanks in advance guys.
 
That is the fuel filter. The vapor lines go to the charcoal canister from the tank.
 
That is the fuel filter. The vapor lines go to the charcoal canister from the tank.
Ok that makes sense but now I’m more confused because that means I have ways too much fuel pressure going to my carb. And you’re talking about the charcoal canister attached to the core support?
 
Ok that makes sense but now I’m more confused because that means I have ways too much fuel pressure going to my carb. And you’re talking about the charcoal canister attached to the core support?
How much pressure is at the carb?

Yes, canister should be at the core support
 
What year is the truck?
Was it originally carbed?
 
That filter and the attached braided hose should be from a TBI truck so if you are still running the electric pump you likely have twice as much pressure as the carb wants.

Fyi, the pressure regulator on a TBI system is built in to the throttle body.
 
you very well could have to much fuel pressure, esp after you replace that nasty looking fuel filter, which probably hasn't been changed in long while. The TBI pump can put out up to 20 psi. Unless the PO added a pressure regulator you don't have one. Best place to add one is between carb and fuel line from frame. You can use the factory return line for excess fuel back to tank.

maybe a regulator like this https://www.summitracing.com/parts/hly-12-887.
I am running a carbed engine with an external electric pump no regulator. This is the pump i am using https://www.summitracing.com/parts/edl-1730.
I did need to lower the pump after this picture was taken. In tank is by far the best location for an electric pump. I would keep the pump in the tank.

IMG_20190605_194134.jpg
 
That filter and the attached braided hose should be from a TBI truck so if you are still running the electric pump you likely have twice as much pressure as the carb wants.

Fyi, the pressure regulator on a TBI system is built in to the throttle body.
Yeah it looks that way I’ll have to put in a regulator, it will be interesting to see how it runs with lower pressure.
 
you very well could have to much fuel pressure, esp after you replace that nasty looking fuel filter, which probably hasn't been changed in long while. The TBI pump can put out up to 20 psi. Unless the PO added a pressure regulator you don't have one. Best place to add one is between carb and fuel line from frame. You can use the factory return line for excess fuel back to tank.

maybe a regulator like this https://www.summitracing.com/parts/hly-12-887.
I am running a carbed engine with an external electric pump no regulator. This is the pump i am using https://www.summitracing.com/parts/edl-1730.
I did need to lower the pump after this picture was taken. In tank is by far the best location for an electric pump. I would keep the pump in the tank.

View attachment 340072
Yeah that filter is the only thing between the tank and the carb. I put in a new sending unit which has the pump attached. I’ll have to put in another filter and regulator I guess.
 
So I’m a little confused now after researching regulators. So the largest line is the “delivery” line (3/8”). The next smallest line is the “return line” (5/16”) and I know the very small line is the vapor line (1/4”). Please correct me if any of that is wrong. So a deadhead style regulator goes on the delivery line right? I don’t see how putting it on the return line would regulate fuel pressure but then again I really don’t know what I’m talking about when it comes to fuel systems. That’s just what makes sense to me. And then how do bypass style regulators differ? I appreciate all the help.
 
All the line size stuff is correct.

I’ve always put a regulator in the return side, all pressure over “X” gets returned to the tank (down the 5/16” in this case)
 
I used a return style regulator- my feed line goes to the reg and then the carb. The reg has a return port to dump the excess back to the tank. Most good regs have a small pressure port for a gauge so you can see / adjust pressure.

FE0CA602-AA23-433A-917F-B92E1DCE9B03.jpeg
 
All the line size stuff is correct.

I’ve always put a regulator in the return side, all pressure over “X” gets returned to the tank (down the 5/16” in this case)
ok I think I’m kind of getting it. Where I’m still confused is I have two lines running into my carb, (delivery and return) so once the fuel reaches the carb wouldn’t it be at whatever psi the fuel pump is? And wouldn’t regulating the pressure at the return line only regulate the fuel dumbing back into the tank? I know I sound stupid I just can’t get my head around the return line part I guess.
 
On a return style, the carb feeds off the back pressure held by the regulator.

The result is the same but an “easy” analogy is either the door is half open (regulator on the feed side) or the door is half closed (return side).
 
ok I think I’m kind of getting it. Where I’m still confused is I have two lines running into my carb, (delivery and return) so once the fuel reaches the carb wouldn’t it be at whatever psi the fuel pump is? And wouldn’t regulating the pressure at the return line only regulate the fuel dumbing back into the tank? I know I sound stupid I just can’t get my head around the return line part I guess.

Post up a pic of the carb and lines. It might help with what you are trying to figure out.
 
Ok this is very embarrassing, my motor is tbi not carbureted. In my defense I was told it was carbureted and I never looked into it, the only work I’ve done to the motor is pulling it. No excuses though I’m inexperienced and obviously couldn’t tell the difference by looking. This actually explains a whole lot though.
F1883942-5F8C-4149-ABF5-2ECFC2B15104.jpeg
don’t crucify me I feel plenty ashamed.
 
Ok this is very embarrassing, my motor is tbi not carbureted. In my defense I was told it was carbureted and I never looked into it, the only work I’ve done to the motor is pulling it. No excuses though I’m inexperienced and obviously couldn’t tell the difference by looking. This actually explains a whole lot though.
View attachment 340150
don’t crucify me I feel plenty ashamed.
Don't sweat it dude. It's all good. You can't know it all right out of the gate.
 
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