Trouble filling up the gas tank

[Goodfootin]

Thank you again! Your write up with pics and labels was tremendous!

 

[treehan77]

Like he said, if you do t have a bench tester for 12v, use the battery and attach some wires. Be careful there. Might want to unhook the - from the truck lol

 

[Goodfootin]

Ha! Yeah, might be a good idea.

Here is another question out of ignorance. Are the leads inside the canister plug interchangeable, or is one positive and one negative? If it matters to which one I apply +/-, how do I determine which one is which?

 

[treehan77]

You could look at the plug that goes to it and determine that way. I don’t remember the colors. If you had a multimeter, you could check that, then do the same on your test. I don’t think it’ll matter for bench testing.

 

[Goodfootin]

I may try to make an adapter for the tank vent line by cutting off the pipe on the old charcoal canister.

This was a brilliant idea. Worked perfectly!

Rooster, your solution for pressurizing the tank and letting it exhale did the trick! The vent line looked like the big black inmate in The Green Mile exhaling the bad stuff. Pellets flew everywhere, and after 3 or 4 times, it was totally clear. Also got a few dozen pellets out of the line up to the purge valve. Refueled this morning with no trouble at all. And Treehan, thanks for the tips on testing my parts. Bought a multimeter and made sure the solenoid and the wiring were all functioning properly.
I'm likely one of the least mechanically savvy people on this forum, but I'm smart enough to know that I'm not that smart, so I don't take risks and screw up my truck. I'm cheap, so I don't want to pay a mechanic a ton of money, and I can read and follow directions. All of you who posted great info in here just saved a high school teacher a bunch of money, and I cannot thank y'all enough. It is greatly appreciated!!!

 

[treehan77]

Glad you got it. Filling the tank for 49 minutes sucks!

 

[DenaliReyes]

What headache , I need to clean the line again. I keep seeing bits of charcoal on the purge solenoid. I recently changed everything is new the purge valve the evap can, the solenoid. I just tried vacuuming the line. Hope this helps but I still hear rattles of bits of coal. Will see

 

[Soop]

Quick question. If you did take it to a mechanic to replace Evap system and lines, etc, what would be an approximate cost?

 

[treehan77]

$1000

 

[stubbs]

Do any of you guys know if this problem also applies to the NNBS Suburbans?

I’ve got an ‘07 2500 (6.0 LY6) that I think is stuck with the same issue. I just went to fill it up for the first time today and found that despite the gauge showing empty, it wouldn’t take more than 31 gallons AND fuel came flowing back out the filler before the gas pump shut off the first time.

Since the 2500 has the 6 gallon aux tank, I’m guessing I’ve got a venting problem somewhere that’s causing the aux tank to not fill and/or the main tank to not vent properly while filling and shut off early. No CEL or any other problems though.