I have a no name 3.5 gallon flush toliet that continues to back up and can not figure why.It is back to back with another bathroon toliet which works fine. Toliet has been snaked out numerous times and even removed to check for debris. Rim holes etc. were all cleaned out.
Does your tank fill up to the mark, is your flapper leaking and you dont know, sounds like you are not getting enough water to flush, is the 1/4″ tube in the overflow a 1/2″, put some egg dye in tank and dont flush and see if the color comes through in bowl.
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