Question– “I replaced all parts within my toilet tank. Now when flushed there is a large air bubble that comes up in the toilet bowl every time flushed. This did not happen before I replaced all the inside parts. I replaced all the inside parts with new parts again, but it did not solve the problem. I replaced all the inside parts in 4 toilets and have this problem on only one.”
We have a couple of questions… before we can answer your question.
1) How old is the toilet? A: 6 ½ Years
2) Have you ever used bleach discs that go inside the toilet tank? A: No
3) Why did you originally change these parts? A: Loud fill… installed Quiet Flush kit
4) Have you recently changed any of the drain lines located in that area of the house? A: No
Based on your responses…
Answer– In our opinion if the air bubbles are bothering you enough then you would need to replace the toilet. This would allow you to know if the toilet has become defective or not. If the air bubbles are still present with a new toilet then you have a venting problem with this bathroom and would need to fix the vent.