I had a slow leak in my toilet which was originating from the base of the "fill tube". in order to replace i bought a flush valve kit and hand tightened as per instructions. I know you dont want to over tighten or you could crack the porcelin and have a real problem. my question is, can i use some plumbers putty under the rubber washers... or do i just need to tighten some more and hope for the best. the problem is you dont know if it is fixed or not until it is all back together. thanks

By "flushvalve do you mean the flapper and overflow assembly? If it's the tank bolts that you're speaking of take a screw driver and tighten them up until the tank has a quarter inck of rock. It's important not to tighten the bolts that the tank has no give at all. The first person that leans back against the tank will crack the china next to thebolts and you'll be looking for a replacement. Good luck, tom