Fuel Tank Pressure and Leaking Gas (1 Viewer)

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I have developed a fuel leak that seems to occur because of too much fuel tank pressure.

If I fill my tank and pull into my driveway, gasoline will start escaping past the fuel cap about 1/2 hour after I park. I'm assuming that this is because the gas is warming and expanding. It does not leak after I run several gallons of gas out of the tank.

I do not understand the rat's nest of hoses in the passenger-side rear quarter panel, but I'm assuming that some of that is to control fuel tank pressure?

If that is the case, is there a control for excessive fuel-tank pressure?

It seems to me that the tank is developing too much pressure and forcing fuel past the filler cap.
 
One of the hoses will be a vent or breather line, I am guessing that after fill up the fuel will slosh around and with no other escape route the fill cap is acting as the vent. Check for kinked or blocked lines in the breather hose
 
overfill? you may need a new OEM gas cap
 
When mine was doing this, I replaced the fuel cap gasket... no change. A bit of reading on mud had me swapping two of the lines at the charcoal canister, no issues since. Not sure exactly what it did (bypass a plugged canister?).
 
Switch the two lines on the charcoal canister. You'll bypass the check-valve in the canister that prolly is no longer working.

Or, if you really want to keep the canister set up, you can replace it with this ONE (linky) and it works perfectly.

Here it is installed in an 80 series:

lc_cnstr.jpg
 
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I had the same problem, i swear mine had spewed gas out of the tank for like 30 seconds straight, wierdest thing. But i changed the hoses around on the canister and no more problems.
 
Sorry for the hijack, but I've got a question for Spike. What can you tell us about that charcoal canister? Is it a drop in replacement for the 60 or 62? Seeing that OE is unobtainium, a decent aftermarket one (and inexpensive, too!) would really help a lot of guys out.
 
Here's the thread in the 80 section: https://forum.ih8mud.com/80-series-tech/412261-charcoal-canister-great-option.html

You'll see it's been used in just about all series 40/60/62/80 ... For the 60 it's drop in other than the ports on the canister are 90 degree, instead of 180 up, like the stock, so you may have to replace some emission hose depending on the length of yours, but otherwise it's drop in. 62s I've never seen but others seem to have done it no problem.
 
Switch the two lines on the charcoal canister. You'll bypass the check-valve in the canister that prolly is no longer working.

Or, if you really want to keep the canister set up, you can replace it with this ONE (linky) and it works perfectly.

Here it is installed in an 80 series:

Thanks for this. If I can't pick up a used one from someone in the Capital Land Cruiser Club, I am going to order this one.
 
Yo.

Take some pix - I don't have any in a FJ62 installation....
 
I have developed a fuel leak that seems to occur because of too much fuel tank pressure.

If I fill my tank and pull into my driveway, gasoline will start escaping past the fuel cap about 1/2 hour after I park. I'm assuming that this is because the gas is warming and expanding. It does not leak after I run several gallons of gas out of the tank.

I do not understand the rat's nest of hoses in the passenger-side rear quarter panel, but I'm assuming that some of that is to control fuel tank pressure?

If that is the case, is there a control for excessive fuel-tank pressure?

It seems to me that the tank is developing too much pressure and forcing fuel past the filler cap.

Had the same problem. Check the filler neck and see if the bottom where the tab to hold the ear on the gas cap is worn. Mine is worn out and the tab is gone. This is a design flaw--had they put th the tabs at 9 and 3 instead of 11 and 5 the gas nozzle would not rest on the bottom tab all the time, thus not wearing it out. Silly Japanese.
Short term fix: Get a second gasket and slip it on the cap, push hard when closing, problem solved.
Long term fix: Got a used filler neck from SOR that's nearly as screwed up as the original, gonna cut the top off and weld on a late model screw-on cap piece. Should fix it forever.
 
FJ62 Canister?

I have a 62 - is this the canister?

I also have/had the same issue w/ gas comming out of the cap when the vehicle is powered off with a full tank. This is from the passenger side:
Canister.jpg
 
Yep, that's it. The new canister fixed the problem, but it does not fit the bracket well. It is a tad larger in diameter and I have it zip-tied to the bracket right now, but the gas is staying in the tank.
 
Switch the two lines on the charcoal canister. You'll bypass the check-valve in the canister that prolly is no longer working.

Or, if you really want to keep the canister set up, you can replace it with this ONE (linky) and it works perfectly.

Here it is installed in an 80 series:

lc_cnstr.jpg

Seems to me there's three hoses coming out of the stock FJ60 can?
Also where does the not-out-of-the-fuel-tank hose go?
 
Yeah, I'm not swapping that rusty bastard canister out, I will pull the clamps and swap the hoses tomorrow and see how that fairs :hillbilly:
 
I have an '83 FJ60. I was getting the fuel smell and a slight whistle. That fit some of the issues described with the bad vacuum canister. Got one of the VC120's from Autozone (its a Dodge truck application I think...)

It seems to run just fine for now. No ill effects. The things I did notice is that the VC120 only has a "Purge" and "Tank" vacuum line location. What I believe is the stock (probably original) canister has two additional ports. One is on the bottom. Haven't tracked where it actually goes yet, but didn't hook it up or plug it. The original canister also has a 3rd vacuum hook up on top that goes to some type of valve or something. I didn't hook that one up of plug the line. I was thinking that if the rig didnt run correctly (or pass smog in a few days because of this) I would cut that 3rd stub/nipple on the canister and hook it up for the check valve. That wouldnt solve the issue of the bottom hook up, but oh well...

Im going to post this response over in this thread too, as it is on the same topic, https://forum.ih8mud.com/60-series-wagons/586004-alternate-charcoal-canister-fj62.html

Any input, ideas or comments are welcome.
 

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