Only able to take 16 Gallons of Fuel... what's up? (1 Viewer)

[Taylorious]

Hi all.
Longtime lurker, and finally got into an FJ60 this summer and have been slowly working out the kinks.

ISSUE:
Of the 'smaller potatoes' is the title issue; I can't put more than 16 gallons (+/-) of fuel into my truck whenever I fill it.

Now, I know the manual states the OEM tank is 23.x gallons, and I don't see any custom work done under the tail, so I don't know what'd cause this issue.

The ONLY thread I've found on mud with any 411 on this is cc'd in the link below:
FJ60 Fuel Tank Capacity

But; I'm curious if anyone'd had this issue before.

MY CURRENT KNOWLEDGE LEVEL:
Poster in aforementioned thread suggests causes as "foaming" / "venting", and suggest dropping the tank to see what's up. I'd believe that a venting /vapor evaporations issue could cause this, as my truck isn't running a 2F, and perhaps doesn't have some vent line or vacuum pressure hooked up which allows for air to escape during fueling...



MY CORE QUESTIONS:
- When I drop the tank, am I just looking for obstructions inside? Or... is there some other detail I could be missing?
- Is there a certain vapor line or seal that could be a culprit here?
- Has anyone else experienced this issue on FJ60/62 trucks, esp. with engine swaps?

 

[FJ60Seth]

Tank venting is into the charcoal canister located on the passenger side in the engine compartment. When it plugs up, gas will spill out the filler neck as the gas expands.

I’m wild guessing that you’re gauge is wrong and your tank isn’t empty.

 

[bigredmachine]

maybe the trucks on a diet

 

[upperblack]

Pull the carpet back in the cargo area to access the top of the fuel tank. Remove the fuel sending unit and look inside the tank and see where the fuel really is when the gauge is showing empty.
Easy way to find out what’s going on and check the the integrity of the tank

 

[cruiserpilot]

Carry a gas can and drive until it runs out, then find out how much it takes

 

[morganism]

I don't like running em out of fuel, injects all the gunk in bottom of tank into the carb system.

Try pulling the cargo panel out on last passenger side, and take a look at the vapor condensor system. Hvnt seen any troubleshooting steps on it, but lots of hose connections in there....

 

[lovetoski]

When my fuel gauge needle sits on the top of E, I have used about 17-18 gallons. Middle of E, and I've used 20. I think you fuel gauge is the issue. It's unlikely the tank shrank.

 

[Taylorious]

THANKS ALL WHO REPLIED!

Tank venting is into the charcoal canister located on the passenger side in the engine compartment. When it plugs up, gas will spill out the filler neck as the gas expands.

I’m wild guessing that you’re gauge is wrong and your tank isn’t empty.

The 5.7L in mine has the canister up front. I've gotten an occasional PO441 code when driving, which went away after replacing an evaporations purge system valve. ...but it came back today. Perhaps there's a plugged canister line from tank to charcoal?

Pull the carpet back in the cargo area to access the top of the fuel tank. Remove the fuel sending unit and look inside the tank and see where the fuel really is when the gauge is showing empty.
Easy way to find out what’s going on and check the the integrity of the tank

I'll do this. Thanks for that!

OP in the thread I cited here said that it was a sending unit issue. Apparently the pick-up didn't reach the bottom or top of the tank, and caused a limited fill. I'll look up this part asap. Thanks all. I'll update as things pan out.

 

[3_puppies]

is it a stock tank?

 

[Taylorious]

is it a stock tank?

It is.

 

[Randy88FJ62]

I'm with the OP, I usually never see filling up over 12 gal when I am at a quarter tank. I plan on rebuilding the charcoal canister this week and I just installed a new fuel filler neck with a new cap and a new neck welded on. Crossing my fingers this will solve a few issues.