How tight can I tighten triangular plastic nuts on a toilet base

Question

My ~10-15-year-old toilet has been leaking around the base lately. Thought I’d try tightening the nuts on the base, and when I pulled the caps off, I was surprised to see the nuts were triangular plastic ones that look like they were designed for hand-tightening only. They weren’t super loose, but could be tightened about one full turn by hand. This didn’t make the seeping stop, though it may have slowed down. They’re still extremely easy to tighten by channel locks, but I don’t want to do that if the nuts are specifically designed this way as a way of telling me “Hey these nuts aren’t meant to be tightened that much.” Unfortunately most web pages and YouTube videos use metallic bolts and I’m not having any luck googling “Why are these toilet base nuts plastic? Is this a warning?”

I’m aware it’s possible my issue is a wax seal or gasket that needs to be replaced, but I’m early in the process of figuring out if that’s it, and want to try tightening the nuts some more before deciding I need to do something more drastic. But on the other hand, I don’t want tightening the nuts to be the reason I end up needing to do something more drastic…

So, how tight can you tighten the triangular plastic nuts? I don’t feel like it’s likely to break the porcelain, but might I end up screwing up something on the bottom side like the flange or seal if I give it a couple turns with the channel locks?

Answer 1

Tightening the nuts will not improve the seal. You must remove the toilet and replace the wax ring. The nuts are meant to prevent the toilet from moving. Although, as you have noted, they are not particularly strong and if the toilet is apt to move you usually need to silicone it to the floor as well. But once the toilet does move, the seal breaks, and you can't fix that by tightening the nuts.

How much can you tighten them?

Step 1) Buy some spares.

Step 2) Don't install the wax ring at first. Tighten them as much as you think is right, then throw your giant ass down on the toilet to see if it moves. If you don't have one, find someone heavier. If it moves, tighten the bolts more. If they break, you know you need more than the bolts to hold the toilet in place.

Step 3) Now install the wax ring, install silicone around the base of the toilet if you determined it's required, put down the toilet and tighten the bolts to the point you determined earlier, either tight enough or not quite to the breaking point. Seal with more silicone for strength and/or appearance if you want.