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Rear gas tank leaks

Joined
Jul 18, 2006
Messages
38
Loc.
Fredericksburg, VA
I finally got my Bronco back from the shop. Washed it real nice;D , filled er' up and noticed/smelled gas. It appears to be leaking from around the sending unit. Can anyone tell me what I need. I assume a gasket and maybe a new locking ring (JBG $7). Anything else to check/buy. My biggest hassel is actually changing everythin out. The PO welded a tow bar that completly in cases the tank, so no removing the tank.

Thanks Guys
 

KevinT70

New Member
Joined
Dec 29, 2004
Messages
85
Loc.
Santa Clara, Ca
That's probably how I'd start. It's not going to be easy with the hitch surrounding the tank. (I had the same type of hitch, but just had it cut off thinking I was going to swap the tank)

I also had the same type of leak but it was actually the pickup tube had detached a little bit at the point it enters the sealing plate part of the sending unit. I replaced the sender and the leak is gone. (If it is the tube, you may want to try JB Weld or something before removing that sending unit--it is not easy to get that seal and ring just right when you're putting it back--an effort maybe made more difficult with your tow hitch).

Kevin T
 

Paco

Jr. Member
Joined
Feb 4, 2005
Messages
293
Loc.
Pueblo, CO
This should help...

http://classicbroncos.com/forums/showthread.php?t=87861

I replaced the seal in mine while the tank was in the Bronco. It was a little tricky holding the seal in position, but not too bad. I did have a hairline crack in the sending unit itself, which I found after I replaced the seal the third time, so check and make sure the sending unit is in good shape while you have things apart. The seals are readily available. My brother used to work at Ford, so I still get alot of my stuff from the dealership.
 
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eds73
Joined
Jul 18, 2006
Messages
38
Loc.
Fredericksburg, VA
Kevin,
Sorry to sound uninformed (although I am) What is the pick up tube? Also What is JB Weld (Maybe thats the Place to buy One:p )

Thanks again
Ed
 
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KevinT70

New Member
Joined
Dec 29, 2004
Messages
85
Loc.
Santa Clara, Ca
That's OK Ed. I think pick up tube is the right term but maybe not. I'm talking about the tube on the sending unit where inside the tank, with a filter at the end, drops down and "picks up" the fuel. Outside of the tank, your fuel line attaches to it with (5/8"?) rubber fuel line.

JB Weld is clay-like epoxy compound that you can buy at an auto parts store. Like clay, you can mold it to any shape and then it turns into a hard "metal" substance. I really don't recommend going that route if you want to do it "right" but it may be the least cost alternative and it might work.
 

68 Broncoholic

Bronco Guru
Joined
May 16, 2005
Messages
1,742
Loc.
WA
A better product than JB Weld is Marine Tex. You can find it in most hardware stores and all Marine stores. This stuff is the goods, its for patching gas tanks and actually hardens in gas! Its a 2 part product, and the catalist smokes when you mix it so its got to be good. When it hardens (i've used it on patching holes) it will spark when you grind on it due to the metal content within. Go get some cause JB weld will not hold for long.
 
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eds73
Joined
Jul 18, 2006
Messages
38
Loc.
Fredericksburg, VA
Well I decided I didnt want to replace the sending unit. So I installed new clamps (hoping it was that simple), cleaned everthing up and found the leak. Its coming from the "two (2)" tubes that exit the sending unit plate (?). Kevin you mentioned one pickup tube & I went to Jeffs Bronco Graveyard & Toms to see what the sending units look like. Both appear to only have one tube exited. It got late so I didnt follow the lines but they both apper to belong. In the event I need to replace my sending unit :cry:, Where can I get one like mine or do I have the right one?

Thanks Ed

By the way, do your wives like the smell of gas as a alternative to Old spice:-[ Wife says I stink?:? I detached the filler hose to syphon the gas, seems there was just enough in there to cover my arm and shirt.
 

Paco

Jr. Member
Joined
Feb 4, 2005
Messages
293
Loc.
Pueblo, CO
eds73 said:
By the way, do your wives like the smell of gas as a alternative to Old spice:-[ Wife says I stink?:? I detached the filler hose to syphon the gas, seems there was just enough in there to cover my arm and shirt.

Ed...when you pull your sending unit... if you hold your face in just the right spot and turn the sending unit in just the right way when you go to pull it out, you will get a face full of gas which BOTH you and your wife will enjoy very much!! Don't ask me how I know!

Sounds like you're going to have to replace that unit. At the very least you will need to pull it to put JB Weld or Marine Tex on the inside to cover those cracks. I used JB Weld on mine over 4 years ago and it's still holding up fine. But I also tried it on another vehicle and it didn't work at all! Call your local NAPA or Car Quest or Vato Zone and see if they carry the sending unit. I get a lot of parts locally when available.
 
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eds73
Joined
Jul 18, 2006
Messages
38
Loc.
Fredericksburg, VA
Well, I was hoping I didnt have to remove the sending unit because of the hitch problem. In the event I need to, I figure I might as well replace it with a new one since the work is all the same. I have a bad feeling I'll need to cut the hitch out though.

Can I put the JB weld or similar product around the outside of the tubes? Or do I have to seal it from the inside?

Also, any info on the difference with the 2 tubes opposed to one? Or can't I see the second tube in the pics from the vendors?

Thanks for the heads up. But as slow as I am I'm sure I'll get to know the taste of gas. :p
 

69 ford

New Member
Joined
Jun 24, 2006
Messages
56
Loc.
Clackamas, Or.
I am not sure about the two tubes but you should be able two see pictures on line at Wild Horses. That is where I got mine. The only thing that was a pain for me was that the gasket did not stay in place. What I ended up doing was putting a small amount of RTV blue on the gasket to make it sticky enough to hold it in place so I could get the sending unit on. Not sure if you are suppost to use RTV but I got frustrated after it kept falling out of place. After got working on it, it was not a hard project. I understand your might be a little more difficult to get at. One thing I should have done before I installed the sending unit was check to make sure that the float is good by testing it. The onther thing to think about is to make sure that everything is clean around the gasket area.

And yes, you will smell like gas.:p
 
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eds73
Joined
Jul 18, 2006
Messages
38
Loc.
Fredericksburg, VA
Spoke with Toms. They said that in 1973 they installed sending units with a "return gas line to allow excess fuel to drain back into the tank". He said they didnt have any sending units with the two tubes.

Does anyone know where I could buy one in the event the "JB Weld" doesnt worK.

Thanks
Ed
 

Paco

Jr. Member
Joined
Feb 4, 2005
Messages
293
Loc.
Pueblo, CO
Ed...here's a few pics from my '74. I replaced the o-ring 3-4 times before I figured out my sending unit was cracked right below the tube and electrical connection. I was able to get the unit out while the tank was in the rig. Hopefully you still have access to it so you can pull yours w/out having to cut out your hitch.

A better alternative than the JB Weld would be to take the unit to a welding shop and have them braze it or weld it. I used the JB Weld because I was in a pinch and it's held up fine for over 3-4 yrs, but if I would have had the time, I would have had it welded ( or brazed or whatever the welding shop said would work best, I'm not a welder)

It is a pain to get the o-ring to stay in place when you're putting it back together. I used a few "small" dabs of Perma-tex 2B to hold mine in place which helped out a lot.

As far as the return tube, I don't know what to tell you. Give Wildhorses, BC Broncos or Bronco Hut a call and see what they say and what they have available. One question I have is do you even need the return tube? Do you have EFI? My '74 doesn't have it, maybe it's not that necessary. My .02 HTH
 

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eds73
Joined
Jul 18, 2006
Messages
38
Loc.
Fredericksburg, VA
Thanks. If the JB weld will last 3 or 4 years. I think I'll go that route for now. Who knows what I'll do with the truck over that period of time. Maybe new bumpers, new 23 gal tank, etc.

At toms, he said I could remove the extra (return)rubber tube and cap the line off at that point or somewhere along the line. Although if I remove it and take your suggestion I guess I could keep it on. Apparantly there is some gas that will come back.

What about soldering the cracks around the tubes? I cant weld but I probably could manage a little soldering. I just dont want to remove the unit If I can help it.

Thanks for all the help
Ed
 

Paco

Jr. Member
Joined
Feb 4, 2005
Messages
293
Loc.
Pueblo, CO
Under no circumstance would I solder it while it's in the rig! I've heard too many stories of gas tanks exploding when guys were welding on them that were suppose to be empty let alone with it sitting there partially full. You might try the JB Weld from the outside, it might work. I applied mine from the inside. Soldering it while it's in a vice away from your rig may work, but keep the torch or gun away from the gas tank!! Disconnect your battery, too before you start so you don't get any sparks that may light up your day!
 
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eds73
Joined
Jul 18, 2006
Messages
38
Loc.
Fredericksburg, VA
As much as I need a tan:cool: No, I wouldn’t have attempted it while still in the tank. I get nervous around it with a screw driver.

Hopefully the JB weld will work from the outside ;D

Thanks for your advice
Ed
 
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eds73
Joined
Jul 18, 2006
Messages
38
Loc.
Fredericksburg, VA
Thank paco. I bought JB today. I'm gonna try that first. If it doesnt work, I'll buy a new sending unit & hope I can get everything in and out ok. If not I'll fill the tank with water (after drying), cut the hitch off and put a new 23 gal in.

Hopefully the JB will work from the outside.
 
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