Smelling fuel (1 Viewer)

[workingdog]

So, there's been a persistent smell of fuel which I finally decided to track down. This truck has been touched (and out of my hands) by several different shops in the last 3 or 4 years. I only recently got it back. One of the shops moved the fuel fill location higher up so I could actually fill the tank, that's when we discovered the rear quarter panels are almost entirely bondo and I ended up with this hideous but functional filler.

However, when I took a look this afternoon, I found what I thought was the overflow return line not plumbed back into the fill neck, but instead it had this on it and it was zip tied to the fill hose. Isn't that a filter?

So, can anyone give me some idea what they were trying to do here?

And, tell me what I should do here?

Clearly, it can't stay like this, it's venting gas to the air all the time.

Peter

 

[pjohnson]

If it is the overflow return line, can you hook it up properly to the fill neck?

 

[reddingcruiser]

This is an auxiliary fuel tank, correct? Is the OEM tank still in place? Normally, the auxiliary tank vent would be plumbed into the OEM tank vent/Evap system, then to a charcoal canister and into the engine air intake system (or a variation of that scenario, depending on the year of the rig). I've seen a similar arrangement where folks think the vacuum valve for the evap system is a filter and replace it with a filter. Maybe someone was thinking along that line.

If this line goes directly into the top of the tank I can see why you are smelling gas vapors. If this is the overflow for the filler neck, it should be returning to the top of the tank from the upper end of the filler neck- without the filter.

 

[workingdog]

No, there is no obvious place to hook it up. The fill neck thing has no place to attach the return line. Isn't this also the vent?

The stock tank is gone. This is the rotomolded Downey style tank.

 

[workingdog]

This is a '66 FJ - I don't think it had any kind of tank vent/charcoal canister installed originally. I'm happy to install the right stuff. There's a 2001-ish 6 liter in this - and I have lots of space. But I'm not familiar with the options.

 

[reddingcruiser]

This is how the later model OEM FJ40 tank is vented. I have a 5.3L in mine and it's set up similar to the diagram. #5 is the overflow that returns to the tank in a stock setup, late model. #45 is the evap unit that takes vapors of the top of the tank and allows them to pass to the charcoal canister and into the engine. #27 should be the vacuum check valve. You can buy charcoal canisters and adapt them for your use. My FJ40 canister has two ports, in and out, making it easy to figure out. You just need to determine the appropriate location on your 6.0 to plumb in the vapor line. Some folks don't worry about this, but I don't like the smell of gas and I want to get every mile I can from every gallon (especially with our new gas 'tax').

 

[workingdog]

Thanks Redding, that's useful. So looking at it now, it's clear I have nothing I need - not even the fill neck is adequate. I have one hose coming off the top of the tank that's the one in the picture. I'm not sure it's the return or the vent. I assume the filter on the end was an attempt to keep s*** from getting in the tank and zip tying it to the fill hose was supposed to get it as high as possible to keep fuel from sloshing out.

So, I'm going to have to start from scratch. I'll get the stock vent thing #45 if I can figure out where I can put it that's high enough for it to work. I'm going to have to replace the filler neck ... again. I'm hoping I can weld in one like the one that came with the Downey tank with a place to hook up the return line. I'll hunt down a simple vacuum actuated charcoal canister. I'm sure I can figure out where to hook it to the 6 liter - that will be the easy part.

But all this is pushing my current skill level.

By the way, #27 is not the check valve, it's a screw. If you know where it is, let me know, I can't find it on SOR

 

[Solace in Solitude]

See @GA Architect 's post# 3 FJ40 Fuel line check valve psi?

 

[Downey]

No, there is no obvious place to hook it up. The fill neck thing has no place to attach the return line. Isn't this also the vent?

The stock tank is gone. This is the rotomolded Downey style tank.

JohnnyC can help guide you to the Downey Off Road link here on Mud, then you will find the installation instruction sheet for the Downey fuel cell, and it will show you the correct plumbing. If this fails, PM me.

 

[workingdog]

Awesome thanks. Who is JohnnyC?

 

[Solace in Solitude]

Awesome thanks. Who is JohnnyC?

Calling @JohnnyC !!

 

[Downey]

JohnnyC has put the instruction sheets on the "Downey Off Road" link, but because I am dumber than an ice cube I have not figured out how to bring up that link- - -but JohnnyC can enlighten you (and me).

 

[workingdog]

I went looking for it. Could not find it.

 

[Downey]

I went looking for it. Could not find it.

I know, me neither.

 

[JohnnyC]

They are in the 25 section... more or less the historical things reside there

Here is the link:
Downey Off Road

 

[workingdog]

Cool - thanks - never thought to look there.