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leaks from bolts under toilet tank

I have tightened the bolts, replaced the washers in the tank, and water still leaks from them. I put plumbers putty under the washers when I replaced them...should I not have used the putty? Any other suggestions for stopping the leaks? Should I try replacing the bolts themselves?

Re: leaks from bolts under toilet tank

Usually you just put a neoprene (black rubber) washer under the head of the bolt. Don't use putty, and don't use a metal washer between the bolt head and the neoprene washer. The neoprene washer should be in contact with both the bolt head and the toilet tank. If you still have leaks, try a thicker washer.

Re: leaks from bolts under toilet tank

Also check the bottom of the tank to make sure you're not just fighting condensation.


Re: leaks from bolts under toilet tank

Take it apart and check for cracks and remove the putty. You might also have a leaking spud and it is running over to the tank bolts and dripping. If it only leaks when you flush it, you can be sure it is the spud leaking, otherwise it may be either.
I would not use a metal washer under the bolt head either, as a metal to metal seal is likely to leak. Besides the neoprene washer under the bolt head, there should also be two more metal washers to use so the hex nuts don't contact the porcelain underneath. Sometimes there are two more neoprene washers to use between the hex nut washers and the porcelain, but not usually. All metal parts should be brass or stainless steel, not plated. Cracks and pitted porcelain can be repaired by drying with a hair dryer to remove all moisture in the porcelain, if there is any rust or scale sand porcelain with some 180 grit paper. Then smear on a a thin layer of silicone and assemble before it starts to set up. Do not move or fill tank with water for 3 hours.

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