Any experience with resealing a gas tank?

[racer_x]

I am in the process of resealing the rust prone tank in my TR8. Originally I was going to have it boiled out as TDSkip had suggested offline. After speaking with a radiator shop, he said it wasn't worth it and if it is rusted I was going to end of with a bunch of holes.
Instead, what i did was place a recipe of chains, nuts and bolts and a container of steel beebes into the tank. I sealed up the fuel pump hole and sender hole with duct tape and took it to work where we have a shaker table used to test packaging.
The shaker table was incredibly loud but did an awesome job removing the rust and varnish on the inside of the tank. It produced some small pin holes, but not very many (maybe 7).
So now I am in the process of ordering an etching acid and tank seal. Has anyone had experience with any of the companies out there?
Anyone have any advice on the process?
I imagine I am going to take some of duct tape and seal the holes up, then rotate the tank around until the liquid has solidified.

 

[hilsideser]

Yes, some. I did 2 tanks about three years ago. I used the white vinegar method; sealed off openings and filled to the top for 2 or 3 days, drained them, put tthe chains inside and sloshed them around to pull off loose scale. I rinsed with more vinegar and gave them another day. It cleaned down to bare metal.
One of the tanks started to leak in a seam. I used the Eastwood tank sealer kit and followed thier instructions. The sealer filled the seam leak and I have had no problems with either tank. Both tanks are in service now. I also redid both vehicles' fuel systems from the tank to the diaphrams at the same time.
I'm going to do the GT6 tank and another Spit tank when it get nicer @ the barn.
Hopes this helps.
Cheers.

 

[tdskip]

I've used KBS successfully but tank didn't really have any pin holes. Kreme etc in my experience won't help you here.

Getting fresh/strong metal in might not be a bad idea John, even if patched on the outside. That, then sealer on the inside and similar KBS/POR15 on the outside would do the trick.

There shouldn't be any vapors left so now would be the time to patch it. I'm expecting to drive the heck out of it once I get back up state NY, so let's make sure this think is solid.

(How nice that for once I'm assigning you work rather than the other way around - LOL)

 

[SkinnedKnuckles]

I used the POR-15 kit to coat the gas tank. There were no pin holes, but it would have filled them using tape on the outside as suggested. Removing the tape & painting the outside with POR-15 afterwards ought to fix it right up. Just don't be wearing sandals and have a drop of POR-15 get between your toes without realizing it....

 

[dklawson]

There have been a few threads about tank lining recently, some here, some in the Spridget forum. It might be worth searching for those to gain the most feedback.

I have used Kreme and POR's tank lining kits. In both instances there were pin holes to seal. Both products are up to the job and the kits come with the prep chemicals you need. I prefer the POR kits because their chemicals are easy to work with and the POR tank lining material is silver in color. Kreme is white and quickly discolors to amber/orange.

 

[Don Elliott]

In 1990, I had a gas tank shop "slush" the interior of the tank for my 1958 TR3A. I had a small pin-hole leak and he said he would not weld or braze it for fear of an explosion. I have driven my TR3A with this tank for the past 19 summers (102,000 miles) with no issues and no leaks. The two part epoxy he used has not peeled, etc. nor has it been attacked by the ethane now used in most gasolines. Also, I have never found any rusty crud or other "stuff" in the glass filter bowl under the mechanical fuel pump, nor in the float bowls for my SU carbs.

For another TR3A I restored, I used the POR 15 kit for the gas tank and have not heard back from the owner about any issues - at all! And none about the gas tank.

 

[SkinnedKnuckles]

I think that's ethanol instead of ethane.

 

[angelfj1]

I would suggest that you use the search feature included above. There have been many discussions regarding fuel tank restoration over the years. We used the Eastwood products for both my TR250 and TR3A. I am satisfied with the results.

Eastwood Link

Another good source is Aircraft Spruce. They're a bit pricey, but they deal with high risk applications.

Aircraft Spruce Link

Good luck.

 

[tr8todd]

TR8 tanks and TR7 FI tanks are hard to come by. They have two holes. The TR7 carb tanks only have one. If your car runs a carb, you can get away with installing a TR7 tank and an aftermarket external fuel pump. You also could install a fuel cell into the spare tire well if needed. Just throwing out some options if you can't find another tank or if yours can't be fixed. I might be willing to sell you a decent used one, but it will be expensive. I plan on taking one out of a 27,000 mile TR8 soon and replacing it with a trunk mount fuel cell.

 

[Deleted member 8987]

A good fuel tank repairman (read: Experienced) would know to feed an inert gas into the tank to braze/solder/weld.
Shadetree, use the exhaust from a running vehicle (no choke).

Seen both ways done, no explosions.

The "old" way of cleaning rusty tanks was a half-shovel of pea-gravel and two guys to shake the tank back and forth.

Done Model "A" ford tanks that way.

 

[racer_x]

I've used KBS successfully but tank didn't really have any pin holes. Kreme etc in my experience won't help you here.

Getting fresh/strong metal in might not be a bad idea John, even if patched on the outside. That, then sealer on the inside and similar KBS/POR15 on the outside would do the trick.

There shouldn't be any vapors left so now would be the time to patch it. I'm expecting to drive the heck out of it once I get back up state NY, so let's make sure this think is solid.

(How nice that for once I'm assigning you work rather than the other way around - LOL)

The holes are minimal, and I can hammer fist it really hard and it doesn't dent. I think it will stand up to your thrashing.

 

[racer_x]

Thanks guys!

 

[TR3driver]

Shadetree, use the exhaust from a running vehicle (no choke).

Or just clean all the fuel out. I used the garden hose to do that, twice now, and it worked out fine. The idea is that fuel floats on water, so fill the tank with water and let it run out the highest spot. Then let it drain and dry in the sun. If you can't smell fumes, they aren't strong enough to burn.

I used ordinary soft solder & a propane torch to do the repairs, plus a patch sheet cut from a tin can on the second one. The second car is long gone for other reasons, but that first tank still holds fuel today AFAIK.

 

[racer_x]

Solder! I like that. It sounds a lot more fun than just sealing it. I think I will do this and seal it. Thanks Randall.

I know the drill for clearing the tank of gas, this was explained to me by on of the panel beaters at Automotive Restorations in CT (when I was working down there in college in the late eighties). I had brought over one of the aluminum gas tanks from a Ferrari 365 that had a loose baffle that was banging around. They told me to heat up and soften the loose baffle to pull it out:

Spoken with an rough Manchester accent, "Run water through it 'till it runs clean. [H]ook up an exhaust pipe from a lorrie [to it] and let it run for a couple of [h]ours. Then take tha torch and [h]old it over the inlet" He was gesturing with his arm out and his face turned away, covered by the inside of his elbow. Then he said "[H}ad one blow up on me. Threw me clear cross the room." Then he smiled.

BTW- The tank was a problem for the car when I purchased it. It wasn't leaking so much as it was evaporating. The problem was clogged fuel filters. I drove one season and several hundred miles with a couple of inline filters in the glove box. I mounted two filters: one at the carbs (clear so I could see the amount and clarity of the fuel) and one before the external fuel pump, mounted on the inner fender. When it would stumble, I would pull over, see the lack of fuel at the filter in front of the carbs, and switch the pre-pump filters. Very easy to do. The clog was caused by very very fine rust.

 

[tomshobby]

I used to repair gas tanks by welding. Probably the first thing to know is that it is impossible render the tank safe from exploding by simply flushing with water. Obviously I never had a tank explode but did have one, very very quickly, increase its capacity once. I had rendered the tank safe to weld on and after some welding I paused the welding too long before continuing. The reason that happened (and I knew better) is that fuel actually permeates the metal and once fuel has been stored in a tank it can never again be trusted to be safe. In other words an empty tank should always be regarded as a potential bomb.
I had included the process in this post and realized someone would surely try it and so removed the process directions.

 

[tdskip]

Thanks for the heads-up Tom.

John, you'd better document all of these and get pictures posted here ;-)

And, with everyone here as my witness;

you said I can drive the stuffing out of your car
you said I can drive the stuffing out of your car
you said I can drive the stuffing out of your car
you said I can drive the stuffing out of your car
you said I can drive the stuffing out of your car
you said I can drive the stuffing out of your car

HA!

(what is kind of funny about this is that when John makes it out West and really gets on whatever I happen to have running at the time I always wince since I'm used to babying them and he just drives - lol)

 

[racer_x]

Thanks for the heads-up Tom.

John, you'd better document all of these and get pictures posted here ;-)

And, with everyone here as my witness;

you said I can drive the stuffing out of your car
you said I can drive the stuffing out of your car
you said I can drive the stuffing out of your car
you said I can drive the stuffing out of your car
you said I can drive the stuffing out of your car
you said I can drive the stuffing out of your car

HA!

(what is kind of funny about this is that when John makes it out West and really gets on whatever I happen to have running at the time I always wince since I'm used to babying them and he just drives - lol)

Yes you can drive the stuffing out of my cars Tom. That is what they are there for.

BTW- I am only trying to find the weak points in your cars so you have something to do.

 

[tdskip]

That doesn't take a whole lot of digging! LOL.

 

[trfourtune]

Re-sealing gas tank.
Here is what i have gone through. I had a tank (non british) professionally lined/sealed to solve a leak. They sand blast the inside completely and drill holes to get the blaster into every spot internally. weld up the holes etc and seal the whole thing, inner and outer. Guaranteed for life.
I asked about kits and they said they CAN work IF the inside is completely blasted (rough) inside. They have repaired many tanks that had a kit sealer job done but fell off inside, plugged up the outlet, and caused all kinds of problems.
At the time it was $200 but a replacement was over $1000. Money well spent said I.
I plan to send my TR4 tank there.(unless i put in a fuel cell-still undecided)
Rob

 

[TexasKnucklehead]

I used ordinary soft solder & a propane torch to do the repairs, plus a patch sheet cut from a tin can on the second one. The second car is long gone for other reasons, but that first tank still holds fuel today AFAIK.

So how big a hole would you patch with solder/tin -or was the repairs limited to the seams only? I've had a tank in the spare bedroom closet for years -aside from the pencil sized hole and cracked seam, there's no sign it's ever had gas in it. I suppose a tank with hole in it has less chance to rust since it dries out better.