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Question about TBP gas tank

Beagleye

New Member
Joined
Oct 7, 2018
Messages
14
Hello
Cutting to the chase- what are 2 extra nozzles beside the fill tube and vent tube on my new TBP gas tank?
Thanks
 

WILDHORSES

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Nov 7, 2003
Messages
2,196
Loc.
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They are for fuel vapor to charcoal canister lines/hose. If you don't need them you can cap them off or we run one into the other with small fuel hose and a couple clamps.

Jim
 

DirtDonk

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Messages
47,345
Even if a cap seems cleaner, do the hose trick instead anyway. The modern caps most available are crap and only last a very short time before cracking. Even when not exposed to fuel vapors!
The hose on the other hand will likely last many years as a "cap" in this situation.

The evaporative emissions vents started sometime in the '70 model year, so if yours is earlier than that yours would not have come with them originally.
If it's a later Bronco though, someone may have simply removed all the stuff as "all that smog crap" instead of leaving the beneficial stuff alone.

What year is yours?

Paul
 
OP
OP
B

Beagleye

New Member
Joined
Oct 7, 2018
Messages
14
Even if a cap seems cleaner, do the hose trick instead anyway. The modern caps most available are crap and only last a very short time before cracking. Even when not exposed to fuel vapors!
The hose on the other hand will likely last many years as a "cap" in this situation.

The evaporative emissions vents started sometime in the '70 model year, so if yours is earlier than that yours would not have come with them originally.
If it's a later Bronco though, someone may have simply removed all the stuff as "all that smog crap" instead of leaving the beneficial stuff alone.

What year is yours?

Paul
Paul

Thanks for additional pointers, that's exactly what I'll do. It's a 68. I am enjoying a little return to the bronco work. I bought it from behind a barn 20 years ago and fixed her up to good functioning farm truck levels right away, but have been neglecting her for a few years now. So I am checking a few things off the list. I sure appreciate all the good advise. I am about to start another thread, but maybe you can help me here.

I need to replace the rear radius arm bushings (C bushings are fine). Can I just gently pull the axle forward with a cam strap to get access to the back of the arm to slip the bushing on?

Thanks so much, Pete
 

DirtDonk

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Well, technically speaking, it's that easy. But in reality-speak it's much more of a pain and takes some balance of finesse and cussing to get the job done.
The key of course is having the right tools to support the frame up higher and the right jack/dolly/whatever to move the axle around. But since it sounds like you've got farm/ranch sense and probably self-sufficient in the tool or "I can make that" department, that aspect might not be too much trouble for you.

You're best off removing the upper trackbar bolt and letting the bar down so it's not fighting you, and the same for the shock absorbers. I've heard members here say they were able to do it with the coil springs still attached, while others (including me) say it adds a layer of hassle.

But maybe others will have some more direct information to add before you get into it that might simplify things.
With the strap arrangement you're talking about, that might overcome any extra force it takes to overcome the hold the springs have.

So yeah, it's doable the way you describe. But I would for sure disconnect the trackbar and shocks.

Good luck.

Paul
 
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Beagleye

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Oct 7, 2018
Messages
14
That's super helpful. It's been years since I changed the coil springs and they're pretty rusty now. Maybe I'll take this opportunity to switch them out. I seem to remember using a system of boards and screws to compress them, but there's probably a better trick. I you tube that. Thanks again!
 

DirtDonk

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Yeah, coils are inexpensive anyway, relatively speaking.
And luckily, they're super easy to change too.

If you're already setting yourself up for a bushing change, you've got all the tools you need to pop a set of coils out in a few minutes.
You raise the vehicle frame however high you need (which isn't much), remove the two bolts holding the top clamp-strap, lower the axle down a couple of inches until the pressure is relieved from the spring, loosen (but don't remove) the two lower clamp springs, and literally "unscrew" the coil from the lower clamp plates.
Voila! Drops right out. Definitely not the same level of hassle as a passenger car, or 2wd truck spring that is soft and under a lot of compression. These 4wd truck springs are still under the weight of the vehicle at first, but they're so stiff that they only compress a couple of inches.

Easy peasy.

Paul
 

quic

Contributor
Jr. Member
Joined
Apr 7, 2011
Messages
63
Even if a cap seems cleaner, do the hose trick instead anyway. The modern caps most available are crap and only last a very short time before cracking. Even when not exposed to fuel vapors!
The hose on the other hand will likely last many years as a "cap" in this situation.

The evaporative emissions vents started sometime in the '70 model year, so if yours is earlier than that yours would not have come with them originally.
If it's a later Bronco though, someone may have simply removed all the stuff as "all that smog crap" instead of leaving the beneficial stuff alone.

What year is yours?

Paul
I purchased a 23 gal tank and am getting ready to put it in, took out the old tank and the vent hose ran up to the differential and ended, its a 77 but the is no charcoal canister or any smog equipment I can see. What would have been beneficial?
 

DirtDonk

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Just in case there are things running all around willy-nilly, there actually IS a differential vent that runs up into the frame. They changed the tank layout on the '77's, so might also have changed the location where the diff vent was clamped to the frame. Maybe someone with a '77 will post up a pic.

For the tank, the charcoal canister really is beneficial. Your '77's filler neck will only accept non-vented caps anyway, so the canister does multiple duties.
But the '76 and '77 setups were also the simplest, so you should be able to set something up easily.
Is there still a steel line clamped to the passenger side frame rail running up to the engine compartment? If so then all you need to do is connect the vent on the gas tank to that steel line, then add a charcoal canister up in the engine compartment.

The style of canister that was used on your '77 is also very easy to find brand new from many sources. Most of them look identical on the outside, but only some have the actual tab for screwing it into the firewall. If you look over on the passenger side of the firewall, you might see a small rib of metal welded to the firewall and a small screw hole in the very top lip/pinch-weld area of the firewall.
The canister sits on the rib and a plastic tab on the top of the canters screws to the hole on the top ridge.

The plumbing runs like this:
1. The small hose fitting on the canister attaches to the vent tube/hose from the fuel tank.
2. The mid-size fitting on the canister is for a float bowl vent, if your carburetor still has one. If the carb was swapped for one without a bowl vent, or if you are running EFI you just cap off the mid-size port.
3. One of the large ports connects to the air filter housing so the fumes can be injested into the engine. But NOT intake vacuum! Just gentle vacuum from the air cleaner side of the carburetor.
4. The second large port is covered (but not closed off) with what we call a "mushroom cap" that lets it breathe, but keeps debris out.
And that's it. For a carbureted engine anyway.

You did not say if you're running EFI or not, but if normal (non-factory functions) EFI you obviously will not need the bowl vent, but you still run the line from the mid-size port to the air cleaner housing.
If on the other hand you're running full factory setup with the computer controlling what's called the "CAN-P" (for canister purge) circuit, you will cover both of the large ports with mushroom caps and use the mid-size port for your purge solenoid to a full manifold vacuum source.
This is the only condition that you would run the evap system to manifold vacuum because it's all controlled by the computer.

Hope that helps.

Paul
 

quic

Contributor
Jr. Member
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Messages
63
Thanks for the info, I will get out to the garage and check, Im running a holley projection throttle body injection, You say I can find a charcoal canister, where to look? rock auto?
 

DirtDonk

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Yep, easy as that most likely. They might even have a listing for a Bronco, but I've never checked that. Hmm, might be a good time so I'll let you know if I find anything.

But other than that, just about every vehicle from '73-ish on to the late-eighties had the same, or similar canisters in use.
I've seen listings showing about a zillion and a half part numbers, but it's hard to tell the difference in most of them since they all look like the same canister size and shape, with only a few slight variations in the orientation of the fittings on top.

Some members here have bought theirs at O'Reilley's and AutoZone and similar shops as well.
If you can't find one with the exact mounting tab on the top as yours would have had, you could easily fab up something out of a small strip of metal you bend around or something along those lines.

I'm still not sure why everyone is so dead set on getting rid of all these things. Seems a waste of time and just shows that they don't realize the benefit of this stuff. Lots of Broncos are found to be missing their critical PCV valves too, just because they were considered some of that "damn smog crap" to some.

Good luck.

Paul
 

DirtDonk

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Did not find it during a quick search on RockAuto. But they're out there. A quick Googling will likely turn up plenty on Amazon or eBay or wherever.

Paul
 

DirtDonk

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Nevermind. I hadn't thought of the fact that all the modern vehicle stuff would be mixed in and make narrowing it down somewhat more difficult.
Lots of modern stuff out there, but none of that would be compatible, or even desirable for an old rig like ours.
Not to mention the price of the newer fancy stuff!

But they do perform an important multi-function lifestyle, and give feedback to the computer on modern stuff.
I'll see if I can find something better.

Paul
 

DirtDonk

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Look at #1 and #8 on this page: Ford EVAP Charcoal Canister for an idea of what the one you want will look like.
Notice the common theme of the overall shape of so many of them, but all the fancy goo-gahs on some are not what we use.
The tops of this one for the Mustangs and the next one for the older Explorers is right up your alley.

Paul
 

quic

Contributor
Jr. Member
Joined
Apr 7, 2011
Messages
63
Paul,
There was a tube on the frame and a lip for a canister on the firewall. the electronic ignition module was mount right there as well.
Thanks for all your help
Andy
 

DirtDonk

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Might be the voltage regulator instead.
From the factory the ignition module was over on the driver's side wheel well (wheel house/tub/inner fender/etc) near the brake booster if you have power brakes.

Over on the passenger side firewall would have been the alternator's voltage regulator (does look similar to many ignition modules, but different once you look closely) for all year Early Broncos.
For the '66-to'72 the location was near the battery, either on the wheel well or more often on the inner fender apron. In '73 they moved it to the firewall to stay clear of the new cold-air intake plumbing. Not sure if they moved it again for '76 and '77 when they put the charcoal canister there, but I bet they at least modified the location.

Of course, some people put their ignition modules over there too, but that's not where it would have been from the factory.
If there is any doubt that any of that applies to your rig, take a pic of the area for us to check out. I'm curious to see exactly where things are mounted myself.

Thanks

Paul
 

quic

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Messages
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I haven't been on here for a while, holidays and such,
I guess the next step is figure out how to post pictures.lol
thanks Paul!
 

DirtDonk

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Welcome back. Pics are somewhat easy, but there are different methods you need to be aware of. Not sure why I never seem to save that thread that shows you how to do it, or how to become a contributor, but apparently I just like to type things out instead!

For some images you can post them directly to your "Garage" in your User CP above.
For the easiest (and best I think) method and to post an image directly from your device you need to be a contributor for 12 bucks a year.
If you prefer, you can use an online image hosting site like SuperMotors and then link the images to your post.

Lots of ways to do it, but it takes some getting used to at first.

Paul
 
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