I flushed the toilet, the water goes down from the tank, but it swirls around and around in the toilet bowl but does not flush. What is the problem. Help.

Our toilet will not flush all the way. We tried shortening and lengthening the chain and that did not help. It looks like the flapper is closing too soon. How can I fix this? Or Do you think this is even the problem?

I have just installed a new toilet / replacement toilet and sometimes it just won't flush. The bowl fills up like it is clogged but it can't be because it is only liquid and no solids in the bowl. When it doesn't flush I notice that if I fill the sink with water and then let it drain out it will...

Every time I flush my toiet cistern, it makes a load groaning noise sounds like there is an airlock. This can be stopped by turning the cold tap on full in the kitchen. How do I stop this problem?? I live in a flat if this makes a difference. Many thanks

I hope someone can tell me what else to try. I am redoing a bathroom in a 50 year cabin. The old toilet flushed strong, but there was a "gurgling" in the other drains. When I removed the old toilet I replaced the flange. The old flange had 3" pvc inserted into the 4" cast drain with some...