Toilet Leak - tank-to-bowl bolt

Hello all.

I am at a loss of what to do with this one. I recently purchased a house built in the 1950s. In the second bath, there's a Sedona toilet that has been leaking. Upon further inspection, I found it's a tank-to-bowl rubber washer that wasn't sealing all the way. The toilet was also running periodically, so I bought a Fluidmaster repair kit and replaced everything, including the tank-to-bowl hardware. However, the leak persisted. It is only a leak from the left bolt, closest to the water supply line.


I've tried replacing all of the rubber washers a second time, and even bought thicker beveled rubber washers but to no avail. I do not see any hairline cracks/chips in the porcelain and scrubbed the area under the washers as best I could.


I don't really want to silicone under the washer, as that seems like a "cutting corners" method - it would be annoying to remove if it didn't fix the problem, too.


Any advice for me? Here's a picture

are your sure it is the tank bolts ?

could it be the big spud washer or nut

Try double nuts
The first one with tank off tighten the bolt with the rubber washer
Then attach tank to bowel with second set of nuts

tanksnotanks said:

Try double nuts
The first one with tank off tighten the bolt with the rubber washer
Then attach tank to bowel with second set of nuts

Click to expand...

I do that when there is room between the bowl and tank.
look for some nuts that are thinner if that is a problem.

I have seen others install the bolts with a metal washer between the bolt head and the neoprene washer before it is installed into the hole.

the neoprene washer has to seal against the under side of the bolt head and the tank. metal washer (brass or stainless steel) only goes on the exterior side of the tank and or bottom end of bolt.