Gas leak question?

[SCRide]

Bronco Gurus

Y’all have been awesome so I’m coming back with another tech question (hopefully one day I will be able to give advice to someone like me!)

About a month ago we started smelling gasoline in our garage where the bronco is parked. When it started, I went under the bronco and could not find a leak. It has gotten progressively worse. When I got back under the truck today, it is obvious where it is coming from. There is a round (approx 2” diameter) disc that has a hose and an electrical looking cable coming out of it in the front side of the gas tank. There appears to be gas seeking all around it and it has taken the paint off the gas pan. What is this piece? Is this something that can be replaced at home? Anyone know of a video/instructions that may exist on the web?

Side note which may be related, my gas gauge stopped working about a year ago.

I have pics but couldn’t figure out how to load from my phone.

Thanks
Steve

 

[gick70]

This piece is where the sending unit is,the gasket,oring probably dried up?

 

[Tugross302]

Sending unit gasket is leaking. Order one of these. https://shop.broncograveyard.com/mobile/1966-1976-Ford-Bronco-Sending-Unit-Rear/productinfo/10212/
Consists of a pick up tube with a filter that sucks the gas out of your tank. A float that raises and lowers with the fuel level. And an electrical connection that tells your gas gauge how much fuel is in the tank. There’s a rubber gasket that seals this to the tank. Evidently yours is dried and cracked

 

[LUBr LuvR]

Welcome to the site and Bronco ownership!

Bet it looks just like this? Going through the same thing right now. The leak is around your sending unit. Could be something as simple as the rubber gasket. But you will need to drain and drop your tank to get to the root of the cause. It’s a good time to check all the hoses, tank straps, components and replace if old or original.

I’ve been wanting to drop and clean my tanks for awhile, plus this sending unit hasn’t been working. After dropping the tank I found a small crack starting in the front/top side radius - not the seams which are more common. Good timing on the Black Friday sales, new tank and filler/vent hoses should be here this week.

To post up pics you can become a contributor for $12 a year. Makes it easy and good way to support this great forum.

 

[gkling01]

I've had these leak from this spot a couple different ways. Oring gone bad and a crack near those connections. If you have a crack and you're in a pinch and have a plastic tank you can do what I did. Drop the tank and empty ALL FUEL from the tank. Important to remove all of the fuel to the point there are no fumes. Once empty and fume free locate the crack. Get a framing nail (16 d or so in size) and heat the head of the nail so it's nice and red hot. Use a propane torch or MAP gas torch. Hold the nail in a set of plyers. Run the hot nail along the crack and it will weld the crack closed. Mine has lasted for 3 or 4 years now.

Good luck and get some PB Plaster or WD40 on those j bolt threads today that hold up the tank as those get pretty corroded over time.

Sent from my SAMSUNG-SM-G928A using Tapatalk

 

[B RON CO]

Hi, my 66 has a rear tank only and you can change the fuel sender pick up with out removing the tank.
Before pulling it all apart make sure the rubber line is not leaking, it could have loose clamps, or a crack.
For some reason I think a metal and plastic tank may use different o ring gaskets
As mentioned, these tanks will drain by gravity, so make sure you are very low on fuel before working on it , the rubber hose, as well as the pickup.
We use a hammer and chisel to gently knock that lock ring on and off, and then the pickup comes out. Look closely the way the lock ring twists in, there is a stop built into the tank. Good luck

 

[SCRide]

I really appreciate your help. LUBR LOVR, I think your pics are what I'm dealing with right now, although mine looks a little different (as could be expected.) I didn't realize the difference in Contributor vs "free membership." I just paid the $12 but still can't figure out how to post a pic. maybe it takes the site a minute to catch up with the payment.

Assuming it is the sending unit, should I drain the tank and then replace it or do I need to drop the tank etc to do this? Is it a "standard type of tool" project or do I need to have some higher level skills?

 

[SCRide]

pics working?

Testing if I figured out how to upload pics.

 

[DirtDonk]

It's a hammer-and-screwdriver type of thing. Tap the locking ring in a counter-clockwise direction to remove it. Opposite to install.

Before pulling it, I would yank the electrical plug off and check it. I see tape there which might indicate an old fault.
If the wiring checks out though, you may want to get a new sending unit with your new seal.

Two tips:
1. Lubricate the seal/o-ring before trying to install it.
2. Connect the new sending unit to the gauge wiring and verify that it reads properly. If not, you can tweak and adjust it now, before installing it.
Saves you a ton of grief over having to do it again when your gauge reads wrong!

Oh, and yours does kind of look like it's a bit hampered by the frame crossmember, but you can tell better from your position whether you think you can remove the sending unit without dropping the tank slightly or not.

Good luck.

Paul

 

[LUBr LuvR]

I read your post too quickly, and missed that it was your main/rear tank leaking. As B RON CO stated, that sending unit can be accessed without dropping the tank. My auxiliary tank is the issue, so yes it does look different (except for the seeping fuel), and has to be dropped to remove the sending unit.

Draining the fuel first will make the job easier.

I’ve had some trash in my fuel filter and tank switching valve, so I’m planning on dropping both tanks and cleaning them and the fuel lines since I’m partially there with the auxiliary out.

There is a specific tool that makes the job easier, but hammer and screwdriver will work too.

Yep, you’ve mastered the photo posting right quick! Good luck with the repair, and post up what you find.

 

[Rustytruck]

Go to Ford and buy the o-ring

 

[SCRide]

About to order the fuel sending unit. This looks like a project that I may be able to do!

Couple last questions:
Can I drive it to use up the gas or is that dangerous?
Do I need to repaint the gas tank where the gas eroded the paint?
Should I buy a new “Fuel Sending Unit Wiring Pigtail?”

 

[B RON CO]

Hi, I think it is weeping slowly, not leaking bad so I would drive it.
Factory tanks are galvanized, not painted.
If your wire is damaged you can splice in the pigtail.
I would probably leave it ( just me).
You can check the wire at the sender 2 ways. If you ground the wire the gauge will go full sweep if all is good. The wire carries a pulsing voltage of @6 volts.
Good luck

 

[B RON CO]

Hi, I got a look at the pics on my PC and it is better then my phone.
I think the lock ring is not completely tight. It is hard to see, but I don't think the stop on the lock ring is against the stop on the tank. If you clean off the dirt you can get a better look. If they are not fully tightened that could cause the drip.
Anyway since you have the fuel gauge problem you may as well change the pick up.
Good luck

 

[DirtDonk]

About to order the fuel sending unit.
Should I buy a new “Fuel Sending Unit Wiring Pigtail?

I would not buy either one until you determine that they are actually bad.
If the connector is buggered, you may not need a new sending unit.
If the electrical tape is just hanging there for no reason other than the PO had at one point held another wire there (not likely, but anything is possible with PO's!) then you may not even need a new connector.
If you haven't already then, you just need to inspect things a little closer.

While Ron is correct that it can be fixed sometimes, if there is a break in the wire too close to the connector to let you get a good connection, then a new one is called for.

Can I drive it to use up the gas or is that dangerous?

I would drive it to use up as much gas as you can. That way not only will it stop leaking most of the time, but it will also keep you from getting a puddle of gas when and if you remove the sending unit.
Definitely check to see if the ring is fully tight, but be careful tapping away with certain tools that can cause sparks.
Knowhatimeantherehoss?

Is it dangerous otherwise to drive it? Of course! But not very...
IN other words, residual gas can still be flammable, but lacking an ignition source, and being so slight, some people can drive with leaks like that literally for years. Months is not uncommon.
But it's still gas, and it's still leaking, so if you are not quite as comfortable driving it as you might otherwise be, spray it down with water before every excursion just to thin out the mix. But I would not hesitate to drive it given what I see in the pics.

Do I need to repaint the gas tank where the gas eroded the paint?

Up to you entirely. Looks like crap sometimes, so yeah, if'n it was me, I'd paint it again.
Looks much better and will hold back any corrosion for a few more decades.
But it's not actually hurting anything.

Paul

 

[VB67bronco]

Same leak happened to my 67... I had to replace the sending unit and gasket on the gas tank.. Since the gas tank was 51 years old I replaced that too.. Not too difficult to do yourself..

 

[SCRide]

Thanks for all the advice.

Have y’all seen this article from Hagerty? Not that I own my Bronco as an investment, but it’s cool to know that it is doing well!

https://www.hagerty.com/articles-videos/articles/2018/10/10/hottest-25-collector-vehicles-fall-2018

 

[SCRide]

Thank you!

Many thanks to each of you for taking time to respond to my original post. Yesterday, my wife and I (yep, we both enjoy working on the bronco), were able to replace the fuel sending unit. We went ahead and replaced the pigtail since it looked pretty worn out. We were able to do all the work with the tank still attached to the truck, and with minimal gas spillage!

The only real hiccups were that the “housing” around the wire was falling apart. I went to the local OReilly and he said it is “asbestos” and they don’t sell it I ended up putting rubber tube around the cable (similar to what the gas flows out through.) Also, I assume there was a filter on the unit we removed but I couldn’t get one out of the tank. Hopefully it won’t become an issue!

Is there a better source for protective wire covering/housing? (Almost all mine under the truck is falling apart and will need to be replaced.)

Pics of the old sending unit attached. Pretty clear why it wasn’t working!

 

[DirtDonk]

Well that seems to qualify for the "has seen better days" category right there!
Glad you had fun fixing it, and without much mess.

The old filter will deteriorate to junk if it has not already. But that actually may have taken place already. But the new sender with "sock" filter on the end should keep it all in the tank.
I don't imagine it will be much of an issue until it gets small enough to pass through the filter. And by then, is it still big enough to cause trouble? I would think not, but then there's always something that tries to dirty up the carburetor!

Paul