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Aux Tank, SAFE? or Potential Fire Hazzard?

77-302

Full Member
Joined
Mar 9, 2012
Messages
315
Loc.
Canton, MI
I have a 1977 with the plastic Aux tank and original rear tank.
The P.O. removed the rubber hose between the filler neck and the Aux tank.
From what I can tell all the parts are still there, Sender, switch on the dash, valve under the driver seat... (minus carbon canister).

I've searched a few of the forum comments.
Some people say they always leak, others say that if God forbid you crashed or was T-boned it would cause a fire, though I don't know how the rear tank is any less vulnerable. Lets face it these trucks (especially lifted) are not known for their excellent safety ratings but we love them just the same.

I was debating getting a 23 gallon rear...

The question is... Do I try to hook up the Aux tank?
Or just take it out...
 

rustbucket

Bronco Guru
Joined
Mar 22, 2004
Messages
1,579
I would remove it and test for leaks before reinstalling it. You should clean it out in any case, as if it's been driven with an open filler, dirt and crud is bound to have found its way inside the tank. I would also replace all the hoses. If the tank is no good, you can either replace it with an aftermarket 12 gallon, or get a 23 gallon main tank. Or both! That way you can get to Ann Arbor, or even Detroit without hitting up a gas station!
 

Chicago71Bronco

Sr. Member
Joined
Jul 23, 2012
Messages
367
Loc.
Chicagoland
I was in a similar situation and put in the 23 gallon tank. Worth every penny especially if you do any highway driving and get terrible MPG like I do
 

AZ73

Contributor
Bronco Guru
Joined
Mar 28, 2012
Messages
3,541
I'm replacing mine as it was all cracked open with one of the newer metal ones. I also put in a 23 gal for the rear. I plan on running it empty unless I'm headed out in the boondocks and need it. At 12 MPG even with the 23 gal your range is only 275 miles. You can run a jerry can but I think you're more likely to get hit from behind than the side. Keep it but don't use it unless you need it.
 

bronconut73

Bronco Guru
Joined
Aug 7, 2012
Messages
9,916
Our auxiliary tanks are not any different than the saddle tanks on Chevy pick-ups from the 70's that the federal goverment found so dangerous.
The only thing protecting either our aux. tanks or Chevys saddle tanks in the event of a crash is the rocker sheet metal.
So you basically have a bomb underneath you in the event of an accident. Hell at best you have gas leaking directly on "you" the driver in the event of a roll over. If I get in a bad wreck in my eb I don't want to be hurt and on fire. I also may have my little girl with me (7 years old) so I may need to help her.....yea...screw that auxiliary tank.
They are only slightly better than the "in-cab" fuel tanks from 50's and 60's pick-ups.
I say get that thing out of there whether you go 23 gallon or not.
 

Z Bronco

Bronco Guru
Joined
Mar 17, 2007
Messages
1,138
I replaced the aux. years ago with a 12 gallon aftermarket (NWMP), this is combined with a 23 gallon rear tank as I have had many moments where I have needed all 35 gallons to make it to the next gas station. The side tank is protected from side impact somewhat by the 3/16" thick 4" square tube steel rocker panel that was welded in place of the original. I do need to make a skid plate for it as there is some rock rash from sliding over rocks. photo-5.jpg
 
OP
OP
77-302

77-302

Full Member
Joined
Mar 9, 2012
Messages
315
Loc.
Canton, MI
Thanks for the input everyone.
You know I actually thought, if I start doing some serious camping, it might be interesting to do a custom stainless tank in this location for fresh water....just a thought....
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,833
There are some HUGE differences between the GM tanks and the Bronco. The GM was protected by little more then the bedside. The Bronco has the rocker panel that is structural to the body. Way stronger.

Have you noticed that almost nobody puts a gas tank at the rear bumper anymore? Some may cry "pinto" but that was the gastank was the floor much like the first gen Mustangs and other Falcon platform vehicles except the pinto didn't seperate the gas tank from the passenger compartment with a trunk. Is there wisdom in a rear mounted tank? Getting rear ended is much more likley then T-boned. Cars like to dive under bumpers, especially those of lifted vehicles. That makes a rear monted tank look like a pretty bad idea.

I have seen a Bronco in a salvage yard that got hit HARD in the driver's door. Without a flinch a total loss bad. No solid reference points to build back to bad. The side tank deformed but held. Answered my question if they are any good, they are. Now aged, brittle, or crusty rusty can change that.

So what's my choice. Dual tanks get to be a pain unless you are always going long distances. Which one are you on? How much is in the other one? Have I gone through the other tank recently enough so it doesn't go stale? How do I plumb a return line for EFI? Single 23 gallon tank does great. Good stout bumper that goes to the bottom edge of the gas tank and maybe even a good tank skid as well.

No reason to get all paranoid over a side gas tank. There is a lot worse out there. But no need to keep the pain in the side either (bad pun I know).

I do like the stainless water tank idea. I would find a better fill location to keep a "friend" from accidently filling the water tank with gas. Nice sealed cap and a light pressure regulator could allow you to use on board air to deliver the water. Why do I suddenly have visions of a drinking fountain on a trail rig?
 

broncnaz

Bronco Guru
Joined
May 22, 2003
Messages
24,341
While the GM tanks did have some issues it wasnt as bad as it was made out to be. a lot of the testing as falsified want to say 60 mintues did some of that false testing as well. They ignited the tanks after the side was hit. Or maybe they reported on how the testing was falseified cant remember.

Basically how I look at it accidents are accidents things happen and few things if anything can be 100% prevented. If it was a big problem on a bronco Im sure it would have made the news back in the day. Pretty much every car out there is a bomb as any tank can rupture and catch fire. So as was said just make sure your tank is in good condition before using it. I have a 23 gallon tank and the aux tank I use them both all the time. its always nice to have some extra fuel.
 
OP
OP
77-302

77-302

Full Member
Joined
Mar 9, 2012
Messages
315
Loc.
Canton, MI
I do like the stainless water tank idea. I would find a better fill location to keep a "friend" from accidently filling the water tank with gas. Nice sealed cap and a light pressure regulator could allow you to use on board air to deliver the water. Why do I suddenly have visions of a drinking fountain on a trail rig?

You could use a lockable cap, I like what you are thinking with the on board air.
Of course that makes me think of filling it with BEER, granted keeping it cold would be difficult.

Getting back to the water idea... 7-8 gallons of water would be nice and leave more interior room for gear. Even if you used it for non potable water.
With my 77, I could run the flowing line right up next to the filler neck and coil it behind the door....hmmmm..
 

crankman

Sr. Member
Joined
Apr 11, 2008
Messages
414
I would fix it in a second. I can think of many times we werent close to any gas stations and limped back on fumes%) I replaced mine with the newer 12gal metal tank and it is pretty stout tank.Put some new fill hose and vent hose check for leaks and you just increased your range.
 

MarkH@Wildhorse

Contributor
Full Member
Joined
Dec 14, 2012
Messages
282
Loc.
Stockton, CA
I own bronco's and Jeeps, the thing that makes me laugh is on the Willy's flat fender jeeps, I've been know to fill them up with gas and not get out of the Jeep. You sit on top of the gas tank. Two of my Jeeps don't even have fuel gauges, I have a dip stick I stick down it, a few times while driving.
 
OP
OP
77-302

77-302

Full Member
Joined
Mar 9, 2012
Messages
315
Loc.
Canton, MI
I own bronco's and Jeeps, the thing that makes me laugh is on the Willy's flat fender jeeps, I've been know to fill them up with gas and not get out of the Jeep. You sit on top of the gas tank. Two of my Jeeps don't even have fuel gauges, I have a dip stick I stick down it, a few times while driving.

Lol, I know I'm being a little paranoid. One day I'm riding my snowmobile at 100mph across a frozen lake with 10 gallons of fuel between my legs and the next I'm worried about a potential crash in a truck that will be babied so much it may never see the rain. I guess it's all relative.... Thanks for keeping me in check. I still like my fresh water tank idea...
 

Ethansdad73

Bronco Guru
Joined
Apr 8, 2008
Messages
1,630
I had a after market 12gal one from duffs on my bronco that i rolled 3x @ 55 landing on the pass side. Nothing leaked or spilled and will got into the truck im building now. I plan to use it more than the 24gal tank as i wont drive it as much kinda a friday sat sun driver.. dontt like having crappy gass sitting to long

Sent from my SPH-L710 using Tapatalk 2
 

Ranchtruck

Sr. Member
Joined
Feb 7, 2008
Messages
766
Lol, I know I'm being a little paranoid. One day I'm riding my snowmobile at 100mph across a frozen lake with 10 gallons of fuel between my legs and the next I'm worried about a potential crash in a truck that will be babied so much it may never see the rain. I guess it's all relative.... Thanks for keeping me in check. I still like my fresh water tank idea...

LOL, well you can roll a snomobile at 100 on a frozen lake and walk away, you can't do that with a bronco. Being strapped in over a burst fuel tank is a little different than being thrown clear.

I had a friend who intended to pass me riding no hands on his 650 triple. Well, one of the ski's caught something and over he went. I got to the other end of the lake and wondered why he hadn't caught up because I was on a much slower sled. I look back and he's doing the shocked drunk stagger and there was sled parts everywhere. We found everything but his ratchet and plug socket and he rode the wreck home.
 
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