Kz1100 Fuel tank leak from side

Hi Everyone,

Hoping someone has some good advice here. I have an '82 Kz1100 A2 Shaft with a nice 5 gallon tank. For years now, gas has been seeping out of the side of the tank where the Kawasaki emblem once was. The tank was spray-painted by a previous owner and you can see the candy red painted some rust coming through a bit as the leaking fuel seems to be deteriorating the wood. I was in denial about the leaking fuel for a long time, but I've come to accept it and am trying to figure out what to do.

The inside of the tank had been very rusty. 2-3 years ago, I had the tank acid washed and coated at a radiator shop when I was in a pinch. I have looked around for a replacement tank, but it's tough to find and the ones I have found are pricy and just as rusty.

I have read mixed reviews about repairing a tank and wonder how that would work now that the entire inside has a coating.

Any help would be awesome!

The inside coating complicates thing. I think it's going to have to be stripped before the leak can be fixed.

No eBay APP ID and/or Cert ID defined in Kunena configurationThis product will take care of the problem. I would remove the tank and lay it on its side, then take a small brush and apply it to the outside of the tank.
I have used it before on a leaking gas tank seam and it stopped the leak completely. It really is hard as a rock when it dries.

That's what I'm wondering about. The inner lining is going to be difficult to remove...

Por Patch SOUNDS like a great solution and definitely worth trying. If I can fix this for less than $20, that's ideal. They say you can apply it directly over rust as well. I would sand off the paint first and get down to the raw metal before trying to apply that though, no?
My worry is that:
A.) I expose a big leak that I may not be able to fix right away
and
B.) the rust that is going through the tank will continue to spread anyway, regardless of what I put on top and I will have another leak down the road.

Have you used this product for a leak like this in the middle of the tank or just for seam work?

Stripping a failed liner is not fun but it is doable. I've had best success with high strength methaline chloride paint stripper. I've read that MEK works well too. To derust I like phosphoric acid. You are going to have to strip off the body mud over the tank badge bars and preferably, remove the bars completely. Small leaks can be sealed by silver brazing or using body solder. Once the tank is fully derusted inside and out then you can apply a new liner using POR-15 or similar. Just don't use Kreem since it's got a pretty bad reputation.

chrisM wrote: That's what I'm wondering about. The inner lining is going to be difficult to remove...

Por Patch SOUNDS like a great solution and definitely worth trying. If I can fix this for less than $20, that's ideal. They say you can apply it directly over rust as well. I would sand off the paint first and get down to the raw metal before trying to apply that though, no?
My worry is that:
A.) I expose a big leak that I may not be able to fix right away
and
B.) the rust that is going through the tank will continue to spread anyway, regardless of what I put on top and I will have another leak down the road.

Have you used this product for a leak like this in the middle of the tank or just for seam work?

I used it for sealing the seam on a gas tank but it will seal anything. It's POR-15 in a toothpaste-like form.
What it hardens, it's like a marble.

You can remove any existing tank liner with aircraft paint remover.

I use Evaporust for rust removal inside of a gas tank. Caswell makes a good epoxy gas tank liner.

Thanks for all the tips. I have talked to a lot of people and looked at a lot of videos and I think clearing out the inside of the tank is not something I want to do...

I think I'm just going to strip all the paint off to the bare metal and see how it looks. Hopefully I can sand it down a bit, put some of that POR 15 on wherever it's leaking from. Prime, paint and clear coat it and call it a day.... for now. I've had such a headache with this gas tank in the past and the person who lined it told me what a pain it was to acid wash the rust out of it - I don't want to go down that path again with the liner.

I'll update later

Any advice for removing the bars?

Seems like they are on there pretty good. I've poured solvent all over it a few times and tried prying them off, but only got the ends to bend up.

I'm stripping the paint now and there's some bonds and a bunch of pin holes. Looks like the bike took a digger or was tipped.
Gonna do a full re-do on the inside. The lining I had has deteriorated and the inside is full of rust... again...

The bracket is dot welded 3 times in to the tank depression.

kzrider.com/forum/6-paint-a-bodywork/612...is-tank-toast#818039

If you pry off the bar the spot welds will tear and you will have holes in the tank. You could try grinding the bar on top of the spot welds, just don't go too deep.

I’ve baked a tank in a powder coating oven then blasted the inside of it out then cleaned it with vinegar. It got one of them cream liners out. The tank looks great now after my first tank paint job. I’d get that liner out if it was mine.
It had a crack across the face of the tank with a dent. So after all the baking and cleaning I braised the crack closed. It worked pretty slick , I wonder if you could do that without removing the badge mount

UPDATE: In case this is helpful for anyone, here is what I did:

I decided to go overboard to make sure I don't need to do this again anytime soon.

I stripped all paint, bondo, inner lining etc. off with KBS stripper, which too a while. Bars were welded on somehow with JB weld or something. I couldn't get them off.

I used POR 15t patch to seal the holes but then read that you cannot sand or dissolve POR15 patch and it looked lumpy and crappy. So I piled on a ton more of the stuff and made a 3D design out of it on both sides of the tank. It doesn't smooth out very well and doesn't seem to like being as thick as I laid it, so it did bubble and streak a bit when it was drying, but I don't mind much.

I cleaned the tank with KBS rust blaster & Evaporust. I found that evaporust (on the outside of the tank) left a black residue that I had to sand off. Pain in the ass.

I used Gold standard tank sealer on the inside. It's supposed to be permanent. It went on well and looks good. It was hard to drain the excess, so I ended up having to use a siphon.

I primed and painted the outside of the tank- Tank and design (bird) different colors. Then I used Spray max 2k clear coat on top of everything. Pretty sweet stuff.

I know it looks pretty armatures but it didn't cost me much but time and I've got something unique that no longer leaks gas (!!!) Can't comment on how this all holds up long term, but thought I'd give this update in case it's helpful.

Attaching a couple of pics here.