Re: Toilet tank bolts rust quickly
Posted by John Scates on November 28, 2002 at 22:08:35:
In response to Re: Toilet tank bolts rust quickly
The rust is coming from a galvanic cell that is set up because you are bolting the steel and brass metal parts together in the presence of water. This happens anytime that you have dissimilar metals in intimate contact while submerged in a conductive medium (in this case, water).

As hj pointed out, the steel washer belongs on the outside. You should have have the parts on the bolt in this order:
1. The rubber washer
2. Through the ceramic tank
3. The metal washer
4. The nut.

- John

: I install new toilet tank bolts and within weeks there is a substantial rust buildup on the bolt heads inside the toilet tank. I'm using the recommended brass parts with stainless steel washers, but the rust builds up anyway.

: The rust builds quickly and builds a pile that is taller than the bolt head in a month.

: What is causing this?

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