Fuel filler issue. This can’t be right.

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AuroraGirl

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I have to hold the nozzle upside down on the 82 for it to take gas without kicking off. But it takes it full flow after that. The 84 I don't have to do this. It just takes it normally. He'll if I know lol
84 had a different filler neck and tank than 80.. but not sure if the 82 was different from the 84. i know the bed mounting is different in 84. (I have a 1984+ bed mounted on my truck, so it doesnt match the filler neck)
 

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@soliddrummer
Agree, you may be able to trim a little off the tank connection side and lower it. I’ve only put one tank of gas in the 77 and it was slow but worked. (Truck came with both tanks full to the brim with no E, great dude I bought it from. )
But before touching anything, unless you’re confident those hoses are still pliable and won’t crack, I’d order and have new matching hoses in hand.
I had trouble finding the right ones (there’s 3-4 different types 70s, 80s, short bed, long bed, and they are basically not interchangeable).
To the point on the 86 that I just reused the old hoses since they were luckily in good shape.
I say this because there’s not an easy mcgyver fix to Jimmy rig the fuel filler hoses with the multiple bends.
 

soliddrummer

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Weird test to your theory, try driving it up on some wood blocks at the gas station and see if the “slope” is really the issue?
Thinking of non destructive tests for what may be fragile hoses.
I like this idea and strangely enough, there were two blocks of wood in the cab of the truck when I got it.
 

DoubleDingo

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I like this idea and strangely enough, there were two blocks of wood in the cab of the truck when I got it.
If you didn't toss them or burn them, put them back in the truck, that's how the PO filled up without backflow issues. If you did toss or burn them, get some new ones and put them in the truck.
 
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Grit dog

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I like this idea and strangely enough, there were two blocks of wood in the cab of the truck when I got it.
Since you mentioned that. I may try it with the 77 just to see.
I could get it to fill, but like I said earlier it was holding the nozzle perfect, standing on one foot and tilting my head or something…
And I ran it empty to check the fuel gauge accuracy so 19.8 gal on slow while doing a yoga pose wasn’t easy!
 

DoubleDingo

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Since you mentioned that. I may try it with the 77 just to see.
I could get it to fill, but like I said earlier it was holding the nozzle perfect, standing on one foot and tilting my head or something…
And I ran it empty to check the fuel gauge accuracy so 19.8 gal on slow while doing a yoga pose wasn’t easy!
Probably easier than under hood head bolt tightening yoga for both banks...lol...
 

Grit dog

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Since you mentioned that. I may try it with the 77 just to see.
I could get it to fill, but like I said earlier it was holding the nozzle perfect, standing on one foot and tilting my head or something…
And I ran it empty to check the fuel gauge accuracy so 19.8 gal on slow while doing a yoga pose wasn’t easy!
And I’ve pumped 100s or 1000s of gallons of gas into round eye squarebodys. But until a couple weeks ago, it was circa 1980-early 90s. Don’t ever recall an issue, but different pumps and nozzles back then.
 

Oldbear42

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I have to back the nozzle out and set the trigger on the lowest setting on mine
That's been a square body issue for decades. We had a couple of bridge planks along our farm tanks (when I was growing up) that you drove the trucks up onto, so they leaned more and let the fuel flow better, but it was still not the greatest and never at flow volume.
 

tanis_46

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my best advice would be to look on lmc and get you a new filler set up.
i have a 77 chevy myself. it fixed a lot of headaches fighting with the old filler hoses.
good luck
 

BadBowtie

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Today's fuel pumps at the stations run a lot faster than they did when these trucks were new-10 years old. We have to run modern fuel station pumps at the slowest setting, and as some have said, pull the nozzle out some to get a nice, smooth, fuel flow.
 

Don-T

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Like most others, I run the pump slow for the best results. I have new hoses trimmed to fit best I could get them.
 

Long Rider

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I have found that holding the filler upside down works for me as well. I have to do the same thing filling the 67 Fairlane and the 58 Biscayne.
 

Grit dog

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my best advice would be to look on lmc and get you a new filler set up.
i have a 77 chevy myself. it fixed a lot of headaches fighting with the old filler hoses.
good luck
I feel like anything OE style would have a similar issue?
 

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