Tank strap issue

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Doppleganger

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The front end of the tank swells in size as it molds into the top / sender. Moving the tank up 5", the front half goes from strapping over the smaller diameter to the larger molded area - plus, the strap is also now perpendicular to the 'swell' and on a slight incline....so the diameter and how the front strap wraps - is different over the larger diameter.

And I did figure it out (I think a couple guys here alluded to what works). Only way I could get the strap to go through the hole and get a nut on, is to put a ratchet strap around the tank behind the front bracket - keeping all 4 bolts on the bracket as loose as they'll go and not fall out (not enough clearance to get the nut in otherwise) - then ratchet/squeeze the tank mount strap in far enough to get the washer and nut started. Cant tighten it all the way as the threaded end will stick out too far and bottom out into the frame....so get it started, then tighten the bracket down to the frame, and THEN tighten the mounting strap to the point its snug/secure but not dug into the frame.

Dumbest arse setup I ever saw. An extra inch of strap and none of this would have been necessary.

I still have another side to go - can get more / better step by step pics.
 

Grit dog

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The front end of the tank swells in size as it molds into the top / sender. Moving the tank up 5", the front half goes from strapping over the smaller diameter to the larger molded area - plus, the strap is also now perpendicular to the 'swell' and on a slight incline....so the diameter and how the front strap wraps - is different over the larger diameter.

And I did figure it out (I think a couple guys here alluded to what works). Only way I could get the strap to go through the hole and get a nut on, is to put a ratchet strap around the tank behind the front bracket - keeping all 4 bolts on the bracket as loose as they'll go and not fall out (not enough clearance to get the nut in otherwise) - then ratchet/squeeze the tank mount strap in far enough to get the washer and nut started. Cant tighten it all the way as the threaded end will stick out too far and bottom out into the frame....so get it started, then tighten the bracket down to the frame, and THEN tighten the mounting strap to the point its snug/secure but not dug into the frame.

Dumbest arse setup I ever saw. An extra inch of strap and none of this would have been necessary.

I still have another side to go - can get more / better step by step pics.

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You’re not listening or I’m not explaining adequately. Although I think it’s the former.
Here’s a pic of the inside of the frame drivers side. Sum ting wong. The strap bolt has to line up with the hole in the frame. That’s how you tighten it. It’s big enough for a socket to fit in.
And I couldn’t get a pic of any of the straps going around the tanks because I have all the tank shields and heat shields in. But to confirm, I was able to reach up in by the front strap and it absolutely sits in the recessed area of the tank. You’re trying to bend the strap around too large of an object, that’s why it’s too short. Only neeed for a ratchet strap would be for new straps that aren’t pre bent. Used straps pop right back in and start a nut on the other side of the bracket.
Look at @CalSgt pics if you don’t believe me.
I just noticed though looking at your original pics…are those thick brush marks in the tank coating or are these some plastic version of the tanks? Maybe they ain’t right….(also suggested that).
 

Doppleganger

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How that centers in that hole is exactly how it sat prior to moving it - the rear sits the same way. Only after moving it does it not fit (and only goes into the top hole). Zero chance it goes to the bottom like it was.

Only thing I can think is that with 100 aftermarket suppliers, are these tanks stamped different? Aftermarket doors can look great but then not line up. The original strap area sat normal - this one will not. I have a ribbon tape measure and am going to see what the difference in diameters is.

Plan B (if I have to move that threaded end to the bottom hole) at this point is cutting the old strap and welding a new one on....extended.
 
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SlickGTP

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Entirely possible that the tanks aren't perfect, but I remember when I installed a new tank on the driver's side of mine that I had to leave the straps started, but loose on the tank while trying to get it into position before starting the bolts on one bracket and adjusting where the straps sat on the tank while getting the other bracket in the right position to start those bolts. It was a three/four way shuffle to get it all lined up and bolts tightened. PITA to say the least, but leaving it all as loose as can be until it was all lined up is what got it done over here.
 

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I don't see how you can get a tank out without undoing the frame brackets first
 

Old Guy Bill

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It's been a while but I don't remember having to bend the tanks much if any.
The pics don't show any...
 

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waterpirate

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My 87 was a pita. New tank and new straps from lmc. Took multiple attempts. One complete do over as we pop riveted one strap inside out. Ughh! Beer and perseverance won out in the end.
Eric
 

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These new tanks are visibly different from the originals. Look at the distance from the sender to the rear and where the original straps were. Also the distance from the rear of the tank and the spring hanger. I almost wonder if I had dual 16's (is that possible?). But the new tanks are definitely different / longer. I may have to fab a custom strap. Also wonder what fun awaits for the filler hoses lining up with the doors on the bed.

This is drivers side only...a couple pics are just to show where the original straps / were.

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Ricko1966

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These new tanks are visibly different from the originals. Look at the distance from the sender to the rear and where the original straps were. Also the distance from the rear of the tank and the spring hanger. I almost wonder if I had dual 16's (is that possible?). But the new tanks are definitely different / longer. I may have to fab a custom strap. Also wonder what fun awaits for the filler hoses lining up with the doors on the bed.

This is drivers side only...a couple pics are just to show where the original straps / were.

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It is very possible you had dual 16s and are going in with dual 20s I made that mistake,but was no big deal. Holes are prefilled in the frame for either configuration. You are going to have to buy vent hoses for 20 gallon tanks.
 

Doppleganger

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It is very possible you had dual 16s and are going in with dual 20s I made that mistake,but was no big deal. Holes are prefilled in the frame for either configuration. You are going to have to buy vent hoses for 20 gallon tanks.
Is there anything in the SROs that would say what it came with? I asssssumed duals would be 20s.

But now this leads me back to where do the straps actually go on these tanks as I was comparing them to the original tanks. I'd like to find a pic of dual 20s exposed.
 

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Come help me pick up the bed and then we'll both know.
Pretty sure these are 20's. I suppose I should find the spec and measure. I think this afternoon I will drop the passenger tank and maybe get lucky getting both today. It's 60° in the breezy shade today.

Looking at yours helps me visualize mine. I'll snap pics from under before I pull the ugga dugga.

On edit - oh, that's a K truck. Not sure if there's differences....
 

Old Guy Bill

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This is a '78 K20, with two Dorman 20 gal tanks.
 

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83Stepper

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These new tanks are visibly different from the originals. Look at the distance from the sender to the rear and where the original straps were. Also the distance from the rear of the tank and the spring hanger. I almost wonder if I had dual 16's (is that possible?). But the new tanks are definitely different / longer. I may have to fab a custom strap. Also wonder what fun awaits for the filler hoses lining up with the doors on the bed.

This is drivers side only...a couple pics are just to show where the original straps / were.

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Went from dual 16's to dual 20's. IIRC there was no dual 20 gallon tank on either short or long bed, but I have been wrong before, just don't tell my wife I said that lol. Problem is the rear bracket should be moved back to the next hole set in the frame, and the front hole and tank strap will fit in the original slot.

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