How to install Cibo overflow waste?

[aussiejosho]

I am trying to install the waste but it keeps leaking. There were no assembly instructions. There were 3 rubber o-rings, am I supposed to use all 3 or is the top one (separate in one image) to be thrown out? I have tried using all three, and only the two silicone ones. I have tried only hand tightened and tightened with a large wrench, niether option works, water runs down the threads over the brass nut. Am I supposed to use silicone?

[MitchellMc]

Welcome to the Bunnings Workshop community @aussiejosho. It's great to have you join us, and many thanks for your question about installing a sink waste.

The water needs to be prevented from reaching the threads of the waste. One of the washers is to go on top of the sink directly under the lip of the waste. So, before you insert the waste into the sink, add a washer to the threaded section. This washer keeps the water within the sink bowl, and it's not able to access the threads. A second washer then goes under the sink on the threaded section before adding the nut. This second washer stops the metal nut from touching the ceramic bowl and prevents cracking. It serves no sealing purpose under the sink. As for the third washer, I'm not quite sure. Only two are required for the installation.

If you've added a washer to the top side and it's still leaking, we'll need to troubleshoot further.

Please let me know if you have any questions.

Mitchell

[aussiejosho]

Thanks for your reply Mitchell.

I get what you are saying and am pretty sure I've done it correctly as you described. It seems the top seal is good because if I push the plug down, no water comes through, but when I pop open the plug, water dribbles down the threaded section under the sink. It seems like when you open the plug, water flows out of the holes in the threaded section (to take the overflow) and from there, the bottom washer can't seal because it is on a threaded surface - not a smooth one. I hope that makes sense....

Cheers,

Josh

[MitchellMc · Accepted solution]

Your test confirms for me that the top washer is sealing; we just needed to work out what the issue was, @aussiejosho. The water is leaking through the outlet threads and bypassing the lower washer. This is a common issue experienced with this type of waste worldwide. Flat washers don't seal threads. You need to apply some thread tape to the portion where the nut screws on. The washers will seal the face of the nut, and the thread tape stops the water from creeping out the threads. 

So, it's a silicone washer on top (which it sounds like you have), a silicone washer under the basin, a plastic washer, thread tape and then the nut screws up over the taped section. I've just checked my waste, and this is the exact issue I experienced. I resolved it with thread tape. I've created the below rendering to illustrate. Once the thread tape is covering the threads, screw the nut up and over it. Tighten with a spanner to compress the washers.

Mitchell

[aussiejosho]

Thanks Mitchell, I'm a bit embarrased I didn't think of thread tape to be honest. I'll give it a go tomorrow but I'm sure you've got the solution there. Thanks again for taking the time. Good onya!

[MitchellMc]

I'm fairly certain I connected my waste without the thread tape the first time and only added the thread tape after it leaked @aussiejosho. I'll pass our feedback on to the supplier, as it sounds like including a small amount of thread tape with the kit would solve this issue.

Please let me know how you go.

Mitchell

[aussiejosho]

The thread tape did the trick. Job done and looks tidy. Thanks again for your help.

[MitchellMc]

Nice work, @aussiejosho! Well done.

Many thanks for letting us know that solution worked.

Mitchell