Fuel only gets to engine when tank is out of the vehicle

[AuroraGirl]

Edit: No she doesn't. The tank is back up but now she is obviously starved of fuel again.

So when the tank is on the floor, she runs beautifully. I then install the tank and she runs immediately afterwards (I suspect that it was just running on the fuel in the lines). This morning I go outside to turn her on and nothing. Cracking, the odd sputter but ultimately no turning on.

I climb underneath the truck and I can freely wiggle the fuel lines so they are not crushed.

Is there any chance the lines are too long and winding? They currently do a loop exiting the fuel tank and connecting to the fuel line. Maybe my pump is not performing as expected, but then why would it work when the tank is on the floor?

This is infuriating!

I will say it again

PICTURES

dont make me get @Rusty Nail in here

clearly, if you said you have a wiped camshaft lobe, youre not going to pump gas Do you have the electric pump used then? The fuel lines if they make an extreme bend or are too long can collapse internally if they are being sucked on by a mechanical pump
Electric shouldnt do that but it would depend on what kind of hose youre using

you also DID NOT have a return line before.are you using a 3 port sending unit but only hooked up to the smaller 2 ports?

go pour a little gas in the carb or using spray, what happens.

 

[Rusty Nail]

Wait a minute...this is the internet still, right?
Pretty schure that's howe it werks...with the pictures AND the letters.
Omg!

Maybe we axe too mush.

We oughta charge moar.

 

[AuroraGirl]

Edit: No she doesn't. The tank is back up but now she is obviously starved of fuel again.

So when the tank is on the floor, she runs beautifully. I then install the tank and she runs immediately afterwards (I suspect that it was just running on the fuel in the lines). This morning I go outside to turn her on and nothing. Cracking, the odd sputter but ultimately no turning on.

I climb underneath the truck and I can freely wiggle the fuel lines so they are not crushed.

Is there any chance the lines are too long and winding? They currently do a loop exiting the fuel tank and connecting to the fuel line. Maybe my pump is not performing as expected, but then why would it work when the tank is on the floor?

This is infuriating!

there is a lot going on in this pic, but pay attention to the fuel lines only

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see how the metal line goes mostly to the tank and it goes all the way to by the switching valve. it was bypassed is why its like that. but that means the driver side tank(In my case) and the loop to gas tank was only long enough to allow connecting while tank was dropped and then raised

You must be registered for see images attach

You must be registered for see images attach

looks like my main one has a loop going on

 

[Challis350]

Ok apologies - pictures coming up!

 

[scrap--metal]

Is there any chance the lines are too long and winding?

Yes!

looks like my main one has a loop going on

Yes, they should have a loop, but it can't be too long.

I previously mentioned that I kinked the rubber lines while replacing one of these tanks before. That happened because I tried to cheat and use extra long rubber lines that allowed me to hook up the sending unit while the tank was still on the ground. When I lowered the tank to fix it, I shortened the rubber lines to reduce the risk of kinking/twisting. I was able to connect the shorter rubber lines while the tank was sitting on the jack, but not while it was all the way on the ground.

 

[Challis350]

Yes!

Yes, they should have a loop, but it can't be too long.

I previously mentioned that I kinked the rubber lines while replacing one of these tanks before. That happened because I tried to cheat and use extra long rubber lines that allowed me to hook up the sending unit while the tank was still on the ground. When I lowered the tank to fix it, I shortened the rubber lines to reduce the risk of kinking/twisting. I was able to connect the shorter rubber lines while the tank was sitting on the jack, but not while it was all the way on the ground.

Interesting. The lines are literally *just* long enough for the tank to be hosed up whilst on the ground (the same length as they were before I removed the tank originally I must add).

I can also freely wiggly the hoses with my hands if I reach up and around so no reason to believe they are kinked.

 

[scrap--metal]

I can also freely wiggly the hoses with my hands if I reach up and around so no reason to believe they are kinked.

Interesting, indeed...

How long did you have it running with the tank on the ground?

 

[Challis350]

Interesting, indeed...

How long did you have it running with the tank on the ground?

Two minutes maybe? It was humming nicely.

There's only so much time I can leave it running as I live in a apartment block in Vancouver and the smell & smoke from the exhaust after a cold start has the neighbours slamming their balcony doors shut.

 

[AuroraGirl]

Interesting. The lines are literally *just* long enough for the tank to be hosed up whilst on the ground (the same length as they were before I removed the tank originally I must add).

I can also freely wiggly the hoses with my hands if I reach up and around so no reason to believe they are kinked.

Those hoses shouldnt be wiggly, that means they will move when put under vacuum and fuel flow. they shouldnt be stiff as a frozen fish but the run of hose should be rather sturdy. A way to help assure that its not the issue is to secure or clamp the hoses to something where bends are or buy hose coil


What SAE number fuel line did you use

 

[AuroraGirl]

Two minutes maybe? It was humming nicely.

There's only so much time I can leave it running as I live in a apartment block in Vancouver and the smell & smoke from the exhaust after a cold start has the neighbours slamming their balcony doors shut.

Its that rich? What kind of smoke at start up? Also pictures

You must be registered for see images attach

 

[scrap--metal]

Two minutes maybe? It was humming nicely.

There's only so much time I can leave it running as I live in a apartment block in Vancouver and the smell & smoke from the exhaust after a cold start has the neighbours slamming their balcony doors shut.

I'm honestly not sure if 2 minutes is enough to be running on fuel pulled from the tank. I would think it is, but I'm not confident in that.

It seems odd that it fails to run when the tank is in the mounted position and it runs when the tank is on the ground. It just sounds like a kinked, or otherwise failing, rubber line to me.

It's nice that you're being considerate of your neighbors, but don't compromise your work because they like their balcony windows open. They live in an apartment. There are aspects of high density living that they will need to deal with sometimes. As long as you have a muffler on the truck, and aren't breaking and rules by working in the parking lot, let the neighbors deal with it.

 

[t44e6]

How can this be if I am able to redline the engine? Surely the engine is getting the fuel it needs?

The idle circuit is independent of the power circuit in the carburetor, you may have crud somewhere.

 

[Challis350]

I'm honestly not sure if 2 minutes is enough to be running on fuel pulled from the tank. I would think it is, but I'm not confident in that.

It seems odd that it fails to run when the tank is in the mounted position and it runs when the tank is on the ground. It just sounds like a kinked, or otherwise failing, rubber line to me.

It's nice that you're being considerate of your neighbors, but don't compromise your work because they like their balcony windows open. They live in an apartment. There are aspects of high density living that they will need to deal with sometimes. As long as you have a muffler on the truck, and aren't breaking and rules by working in the parking lot, let the neighbors deal with it.

It must have been getting fuel from the tank because the engine was starved of fuel when the tank was attached. it's been up and down a few times now!

 

[Challis350]

I will post pictures on Wednesday - It's my "work from home" day.

 

[DoubleDingo]

I will post pictures on Wednesday - It's my "work from home" day.

About time. Pictures provide a wealth of information for those that are trying to help out. A little tid bit for next time, take the pictures before creating a thread of your problem and attach them before posting the thread, that way we won't rag on you to take them. Not only do we like photos, but, as said, they're a huge help. And don't take them with your potato, use a decent camera.