Gas Tank Repair Advice
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From: Grand Rapids Michigan
I've already got it wire wheeled down to bare metal, which is why I'm dealing with a nickle sized hole now. 
Gas tank/rubber gasket/metal plate/covered with lots of goop as a preventive measure. That's my plan, I'll let you guys know how it works out.

Gas tank/rubber gasket/metal plate/covered with lots of goop as a preventive measure. That's my plan, I'll let you guys know how it works out.
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From: Grand Rapids Michigan
Okay, I finally got a chance to work on this a bit tonight. And, like most good battle plans, they never last once you have met the enemy. So, I changed the plan a bit along the way.
Here you can see how big the hole really was once I "cleaned it up". (pic 1)
If you look closely, you can see that the area is actually dented in. I figure it must have gotten banged up a bit, which allowed the corrosion to set in.
I started out by laying on some J.B. Weld, just smoothing it on around the area that I was working with in order to give future layers something to bond to. But before I did that, I cleaned it up with a wire brush followed by some acetone.
Here's the first layer: (pic 2)
Next, I trimmed up some small pieces of sheet metal, and pressed them into the putty in order to cover up 99% of the gap: (pic 3)
Not very pretty, I know, but it ought to do the trick I think.
Next comes another layer of putty, and then I'll leave it alone for a day or so before I add some more layers and widen the area of covereage: (pic 4)
Here you can see how big the hole really was once I "cleaned it up". (pic 1)
If you look closely, you can see that the area is actually dented in. I figure it must have gotten banged up a bit, which allowed the corrosion to set in.
I started out by laying on some J.B. Weld, just smoothing it on around the area that I was working with in order to give future layers something to bond to. But before I did that, I cleaned it up with a wire brush followed by some acetone.
Here's the first layer: (pic 2)
Next, I trimmed up some small pieces of sheet metal, and pressed them into the putty in order to cover up 99% of the gap: (pic 3)
Not very pretty, I know, but it ought to do the trick I think.
Next comes another layer of putty, and then I'll leave it alone for a day or so before I add some more layers and widen the area of covereage: (pic 4)
Personally I would have a new patch brazed on. At this point, you will need to seal the inside of the tank where the J B is. My biggest concern is the overflow tube has lost a good deal of support metal. If there's too much vibration in that hose, it will fail.
the repair isn't bad. crude but effective is what i would say..i would however source a new tank and in the meean time, use this as a temporary spare until a better tank from out west or down south arrives. i've not had great luck patching tanks.
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From: Grand Rapids Michigan
I figure that if this repair does not hold, I can cut the area out and have it welded. But before I do that, we're going to find out how the JB Weld holds up under this type of use. They claim that it is impervious to gasoline. Here's a clip from their website:
Mechanics -- you can use J-B WELD with confidence. It is designed for safe, reliable, permanent repairs in engine compartments and heated environments up to 500° F. It's strong as steel and impervious to water, gasoline, chemicals, and acids. Working with J-B WELD is quick, easy, and convenient -- and saves you time, work, and money
So, we're going to find out if it is true or not. If anyone sees me spewing gas out the back end while hitting the right hand turns on the dragon, then you may all procede to laugh at me until I go home.
Mechanics -- you can use J-B WELD with confidence. It is designed for safe, reliable, permanent repairs in engine compartments and heated environments up to 500° F. It's strong as steel and impervious to water, gasoline, chemicals, and acids. Working with J-B WELD is quick, easy, and convenient -- and saves you time, work, and money
So, we're going to find out if it is true or not. If anyone sees me spewing gas out the back end while hitting the right hand turns on the dragon, then you may all procede to laugh at me until I go home.
Good luck hope it works Kentetsu but I've had jb weld completely dissolve away when I used it in a carb. About 10 years ago they changed their formula to make it more enviromentalist friendly and after that it wasn't as strong. There's better stuff out there.
Thread Starter
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From: Grand Rapids Michigan
Well, even if I have to pull it back out and have it welded next year, at least all of the bolts will be well greased now.
Also, I'm hoping that since the epoxy will have a couple of weeks to cure before it ever sees any gasoline, maybe that will make a difference too.
Also, I'm hoping that since the epoxy will have a couple of weeks to cure before it ever sees any gasoline, maybe that will make a difference too.
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