Fuel tank question #3 this week!

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Grit dog

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In keeping with the fuel tank threads recently, lol.
I got a free tank to replace the rotted out one on the ‘86.
Spent a couple hours acid washing the inside, flushing, drying out, installed sender, ready to reinstall.
I dumped a little 2s oil and gas in it to coat the inside since it won’t be full of gas for a while and then noticed that the fuel filler hose barb on the tank is about an inch smaller than the existing ones on the 1986 tanks!
Fck! I wouldn’t have wasted all that time over a less than $100 part if my dumb arse had noticed that sooner!
So what gives? This tank appears “newer” looks like factory applied undercoating similar to bed liner material. Did the late 80s TBI trucks get a smaller fill hose or something?
Oh well. Free long bed tank to anyone who wants to come pick it up....Holds gas and looks nice...if you can use it.
 

Blackbeard44

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what size is the filler hose?? I have spare tank that I was planning on using to mock up a hanger with a pump on it.

i will measure mine and if it is what you need we could trade
 

TubeTruck

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I know the 70's trucks (at least the Suburban) had a smaller fill hose. I bought a tank for an '87 and it has a 1-3/4" fill hose and my '78 tank has 1-3/8".
 

Grit dog

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Original tanks are 1-5/8” OD on the filler neck and this one is 1-3/8” OD.
 

Grit dog

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Edit: Tubetruck nailed it while I was typing. Older style tank = smaller fill hose.

So with a little GMSB knowledge base googling, one of the knowledgeable members here posted (7 years ago) that 73-81 models had a 1-1/4” filler neck and 82-87 models are 1-5/8”.
So I have an older model tank.
Considering the difficulty in getting the right filler and vent hoses, (Truck Shop sent wrong ones and 1 back ordered)
And since the hoses are all in great shape on mine, a new tank is in order.
 
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Grit dog

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what size is the filler hose?? I have spare tank that I was planning on using to mock up a hanger with a pump on it.

i will measure mine and if it is what you need we could trade
Where are you at? I’m wet side, Seattle area.
Appreciate the gesture.
 

Blackbeard44

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Definatley not 1 5/8 filler hose, im down in Packwood, ocassionally go to chehalis

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Grit dog

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Yup that’s the smaller filler like mine.
Thanks though!
Love that area down by you. Spent a summer working on US 12 by Rimrock in 2018. Awesome country!
 

Dave M

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If it gets you out of trouble, how about fitting a copper reducer in the filler hose with a couple of hose clamps.

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Bextreme04

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I was gonna say you could have my tanks, since I’ll be pulling both for a single TBI blazer tank.... but mine are 1980 tanks, so I’m no help. Sorry man
 

Grit dog

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If it gets you out of trouble, how about fitting a copper reducer in the filler hose with a couple of hose clamps.

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thought about something like that, but the hose makes a hard 90 right out of the tank. And not really wanting to half @ss it.
Can get a new tank for $55, under $100 shipped. I’ve got more time than that fcking with it now! Lol
 

Dave M

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I went through the reverse situation with my tank. The actual tank had the larger neck and the filler tube was the early small type. Fortunately I bought a new small hoses which was pliable enough to stretch over the larger neck. I was lucky to have purchased my parts earlier, as nobody seems to now have stock of any fillers or hoses. By choice l wouldn't want to cut up a new hose either.
 

Grit dog

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^Yes, thinking I’m glad my existing hoses are good shape.
Just getting a new tank and will be done with it.
 

emoze

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i'd guess that "problem" is about the mandated switch from leaded to no-lead fuel & smaller dispenser nozzles; dunno what year that happened but likely it would narrow your replacement searches
 

Grit dog

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^ Hey thanks.
Got the new tank already. Those are dime a dozen fortunately.
 

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