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How to fix trickle in Caroma cistern?

duane1
Just Starting Out

How to fix trickle in Caroma cistern?

Well, I am wondering if there is any hope. I bought the replacement washer and installed it - see red washer in pic. I also bought a black one and tried it but the red one seems a better seal. There is still the slightest of trickles running down the back of the bowl. You wouldn't even notice it, except that from time to time the water drops low enough for the float to cut on and you hear water run for a bit.

I'd like to fix this!

Eric in another post mentioned calcium build up - I can dismantle it again and see if I can spot any. 

Also the spring idea, I suppose that if there is a missing spring it could apply some downward pressure. I didn't spot that either.

Is there anything else to try here, or do I need to move on to the Thunderflush replacement for the dual flush mechanism? 

 

btw the washer does not look completely round when installed as pictured. It is quite tight and for the life of me it always skews a bit no matter how I tug at it. All the best--IMG_20250713_111617.jpgIMG_20250713_111648.jpg

JacobZ
Bunnings Team Member
Bunnings Team Member

Re: How to fix trickle in Caroma cistern?

Hi @duane1,

 

Welcome to the Bunnings Workshop community and thank you for your question.

 

There are two things that look a bit off to me. The first is the amount of space around the washer. 

 

 

When you removed the original washer, did it sit in from the outside edges that much?

 

I would expect to see the washer fill the base of the flush valve. 

 

Can I ask you to give me the outside diameter and inside diameter of the actual flush valve?

 

Are they close to this?

 

 

 

If the washer still makes a solid connection with the outlet pipe, this might not be an issue, but it certainly doesn't look right to me.

 

The next thing I notice is that if you look through the translucent plastic that half of the washer is not tight around the centre of the pipe.

 

 

Try grabbing a flat implement like a butter knife, slipping it under the translucent piece and working the washer back towards the centre of the pipe. If you leave the washer on the flush valve and soak the washer in some warm water for a while to make it malleable, this might help.

 

If this is not working, try removing the washer and giving the seat a good scrub. Like Eric has mentioned in other posts, if there is any limescale under the washer, it can prevent the washer from creating a good seal.

 

If these two troubleshooting efforts do not work, the seating washer might not be correct, or you might have to replace the valve altogether.

 

Let me know how you go and please reach out if you need more assistance.

 

Jacob

 

AlanM52
Amassing an Audience

Re: How to fix trickle in Caroma cistern?

Hi @duane1,

 

Reinstall the washer using silicone spray-

Remove the washer and check again everything is clean.

Hold the valve in such a way that you can rotate 360° in one go.

While rotating once give it a spray.

Centre the washer then proceed in the usual way to finish.

 

It's all about the static vs kinetic friction thing (in this case static).

As you centre the washer the silicone spray will negate the static friction and it will settle nicely by itself.

 

Cheers

 

 

 

 

duane1
Just Starting Out

Re: How to fix trickle in Caroma cistern?

Thank you @JacobZ and @AlanM52 for your replies. I have had another go at it.

I took the mechanism out and removed the washer. It comes in at 66mm OD. Very similar to the one I removed, though that one was black and had gotten thin. 

I cut a bit of wood at 66mm and laid it across the opening at the bottom of the tank. As you will see in the pic. 

The opening itself is around 54mm. I then had a better run at replacing the washer. I sprayed some CRC and pulled until it looked snug all around. The outside edge is still a bit lopsided, but snug in the middle. I replaced and it is much much improved. A slight drip down the back but miniscule. 

Happy with this outcome!IMG_20250722_203321.jpg66mm stick over 54mm outlet66mm stick over 54mm outletwasher seated better I thinkwasher seated better I think

 

 

 

EricL
Bunnings Team Member
Bunnings Team Member

Re: How to fix trickle in Caroma cistern?

Hello @duane1 

 

It's good to hear that you've sorted it out. Hopefully the seal in time will self-centre and the leak will stop.

 

If you need further assistance, please let us know.

 

Eric

 

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AlanM52
Amassing an Audience

Re: How to fix trickle in Caroma cistern?

@duane1,

 

Well thought out and pretty sure when the washer beds down that drip will begone.

 

Cheers

 

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