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- Location
- Portland, OR
Hello, I noticed when fueling my LMTV there was a lot of hissing when opening the fuel cap. I was also having a very subtle idle surging issue and while reading posts I saw mentioned a clogged vent several times. I did a little digging on the forums and couldn't find any pictures or good description so I went on a treasure hunt myself on my truck, and figured I'd write a post to save someone else some time chasing hoses through the frame.
The vent line is indicated in the following pictures. I just used 2 13MM open end wrenches to loosen the hose at the tank. As you can see, the vent line is looped back under the spare tire, and I think that is where the mud wasps or whatever made their nest. At first I though just the end was clogged, but after putting a 4" drywall screw in there and scraping out the crud, it was still clogged! I was able to slip the vent line out of the zip-ties and straightening it out seemed to break up the crud. I was holding the end of the line when my helper hit the air and I got quite the sand-blast into my hand. Gotta love the 180psi shop air... Anyways, cruised the truck for a while and pulled the fuel cap, and no more hissing.
The vent line is indicated in the following pictures. I just used 2 13MM open end wrenches to loosen the hose at the tank. As you can see, the vent line is looped back under the spare tire, and I think that is where the mud wasps or whatever made their nest. At first I though just the end was clogged, but after putting a 4" drywall screw in there and scraping out the crud, it was still clogged! I was able to slip the vent line out of the zip-ties and straightening it out seemed to break up the crud. I was holding the end of the line when my helper hit the air and I got quite the sand-blast into my hand. Gotta love the 180psi shop air... Anyways, cruised the truck for a while and pulled the fuel cap, and no more hissing.
