New toilet leaking between cistern and toilet

[compact]

I have fitted a new toilet.

Between the cistern and toilet, there is a foam ring.

On either side 2 long screw threads.

I fixed these into the cistern firmly (with rubber washer and metal washer inside).
I slotted the cistern onto the toilet and start tightening up.

equal turns on the wingnuts on the screw threads on each side.

There was a small leak combing out.
So I took it off tightened everything and did it again.
This morning there is a slight drip down one of ther threads.

I think it has come from the foam donut.

My questions are

1)How tight do I tighten the wingnuts, compressing the donut?
2)Once compressed once, can I easily get a fresh one to try again (did not pop back to original shape after first try)
3)Any other ideas or advice?

 

[ChrisR]

The leak can be either the donut or the screw holes. Make sure the washers and nuts are in the right oirder - should be a nut under the cistern on the threads.
Yes the foam ones are available easily.
If it leaks when it hasn't been flushed, it ain't the donut.

 

[compact]

Cheers for the reply

The long threaded screws I have them in the right order i.e vertically down.
Screw head (actually a bolt head), metal washer, rubber washer, cistern, metal washer then bolt).
Actually, should there be another rubber washer on the outside before the metal one? (can't see why)
p.s. the rubber ones are the cone shaped ones.

It is hard to see where the leaks is and when, as it is so tiny, it showed after a few hours of use and only is enough to fill half a shot glass after 24 hrs (or enough to wet the newspaper I laid to check).


Will probably take the whole thing off dry off, replace 2 rubber washers and the donut to be safe.

How tight do you tighten on the wingnuts to compress the donut?

As tight as it goes?

 

[AlF2008]

I'd take the cistern off and check the holes for any imperfections which might be stopping the washers from sealing. They shouldn't need to be any tighter than you can do them by hand. the rubber washer should flatten down as its compressed and make the seal.

Normally there are only washers on the inside of the cistern.