It has a very thin crack. I used epoxy and it worked for a while ( a few hours) and then started leaking again. What would be the best product to use for this? I keep thinking about that Flex-Seal commercial!
It has a very thin crack. I used epoxy and it worked for a while ( a few hours) and then started leaking again. What would be the best product to use for this? I keep thinking about that Flex-Seal commercial!
get the inside of the tank dry for a good 24 hours, then use 2 stage epoxy, keep dry for 48 hours then increase the amount of fiber in your diet to prevent further issues.
Any reason for not taking the hint and buying a new toilet before the disaster? Have you seen the water damage that happens when a tank breaks and you are away at work?
By the way, learned that when it does break in the middle of the night, and the shut-off does not work, the fastest way to get a plumber on site is to call your insurance company; at that point its their money that is getting spent and they have people on speed dial. I wish I did not know this.
In reply to captdownshift:
That's exactly what I did that didn't work.
In reply to NOHOME:
The toilet is almost new. It got "tweaked", which made a hairline crack that leaks. Why is it some people can't just answer the question? 
Brand new but broken is still broken. Fractured ceramic will always be fractured ceramic. Sorry.
In reply to KyAllroad:
That's a defeatist attitude, my friend, and it has no place in an optimistic thread as this.
I think you know what you have to do:
The optimist in me believes you will come to the realization that patching a toilet tank is probably futile and go get an unbroken one.
In reply to thewheelman:
I'm pretty sure it will work if it works.
Cheapest fix by far 
shotgun
I cracked a plastic toilet tank. Fiberglass repair is holding up after several years.
Porcelain tank? You are an optimist.
Porcilin? Know any dentists?
Bite the bullet and buy a replacement tank.
Permatex Black RTV. I put that on everything.
Okay, an apparently stupid question - Why is porcelain so hard to seal? Or is it the chance of it continuing to crack after the repair?
New tank.
Now, if you FEEL LUCKY, they make a flowable RTV sealant that I think is marketed for windshields. The guys on the HD site say that you can get it to flow into a base gasket and it will stop the typical leak that all Evo's get at one time or another, between the cylinder and the block. You could try that, but by the time you take the tank off, clean it, dry it, buy the RTV, put it on, let it dry, etc., that $35 amazon purchase looks pretty good.
Instead of replacing it- get it nice and dry, put some brand new ceramic into the crack, and bake at 1400C for a while. That will set the whole thing solid again.
That's how you might be able to repair a crack in ceramic.
Datsun1500 wrote: A new tank is $32 on Amazon. Not worth even trying to fix.
It is if you can't wait for it to arrive.
Super thin cyanoacralate. It will wick into the crack and seal it. Get the good stuff, not the cheap "super glue."
You guys are just making me more determined to find a way to seal the leak. Seriously, its not pressurized, and although i know there is head pressure, still nobody has told me why I can't fix a leak in a ceramic toilet tank.
Is the crack visible when the tank is installed? I keep thinking that since ceramic is porous so when you seal it on the inside water leaks around your patch through the ceramic itself. If you seal it on the outside you might have a better chance? As long as the repair is out of sight you might be okay.
3M Marine 5200 sealant will permanently glue owl E36 M3 to icecubes and is rated for use below the waterline, but it's white. After my experiences using that stuff on boats and the roof of my popup camper, that's my go to when it absolutely, positively has to be sealed and I never intend to remove it.
Hey, speaking of marine adhesives, Red Hand. That's what you need. That stuff was holding the US Merchant Marine fleet together.
bravenrace wrote: You guys are just making me more determined to find a way to seal the leak. Seriously, its not pressurized, and although i know there is head pressure, still nobody has told me why I can't fix a leak in a ceramic toilet tank.
Two reasons really. One is that porcelain is a ceramic which is fired in a kiln. Once cracked it will never be exactly the same and while it could theoretically be superglued back together (if you could get the glue to wick completely into the site of fracture), as long as there was ANY flaw or imperfection you are running the above mentioned risk of water damage (theoretically tens of thousands of dollars). All to prove a point and save the $32 it costs to buy a new one.
Broken windshield: replace.
Cracked brake rotor: replace
Broken toilet tank: sorry, I don't want to sound defeatist and I do understand the urge to be able to fix anything but given the risk/reward ratio, replace.
we're entering hootus warning territory with these suggestions.
You'll need to log in to post.
