i've posted a few today i am sorry if i am annoying you all!! basically though i fitted a new siphon to my toilet about 2 weeks ago. it was a standard 8" one from b & q. i fitted it using waterpump pliers, etc. the prob is when i flush it hard the lever bangs on the cistern lid a bit. i think the new siphon has a thicker washer that joins the siphon to the base inside of the cistern) than my last one!!! this of course making it do what it does when flushed!! anyone else had this problem? can i just switch the washer for a thinner one of: (1 1/2")? ANother prob I discovered when doing this was the doughnut washer split a little bit when i replaced the siphon. then it leaked through the wing nut holes when flushed. so i tried a new doughnut but this was not fitting (too big)!!! i also bought this from b & q! is there anyway i can get a smaller (thinner) doughnut washer - as b & q only do 1 size i had ti use some putty around the crack in the original fitting doughnut to stop the dripping (and it worked after a lot of work)!! but if i change the siphon again for the original problem mentioned, i may have the same problem again with the drippin!!! long post sorry! .....