How to fix a leak on a W C flush pipe, pan end or the cistern end

Leaks on flush pipes are a common problem, I will take you through how to fix them.
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[@garyscott4094]

You are an absolute life saver. Thank you so much for getting straight to the point and being clear about the fine points.

[@dereton33]

No problem Gary

[@tillymint1958]

Thank you so much. Helped me sort out my leaky loo myself. Love the way you explain things in such a straightforward way.

[@dereton33]

Thank you.

[@OldRaver]

Thank you! Just saved me £80 getting a plumber out for a really easy job for my 94 year old dad! ❤️

[@dereton33]

No problem.

[@artistocracy]

Thank you, from me in South Australia! Ours is dripping from pan end, after years of working fine, but our nut is on so tight we cannot turn it and I needed to learn all I could before we begin. Your demonstraction and instruction has helped enormously.

[@dereton33]

Glad to help

[@drclean5728]

Thank you so much - you’re like the plumber uncle I never had

[@dereton33]

No problem.

[@huwthomas4728]

Great advice. My problem turned out to be a perished washer on the cistern end causing water to leak every time we flushed. As I had purchased the pipe and all the other bits needed which only cost £8.50 I changed everything which took about half hour. Thanks and keep up the good work.

[@dereton33]

+Huw Thomas . Thanks Huw.

[@annejohnson952]

Thanks for this video. Extremely helpful and gave me the confidence to try and change my flush pipe. Had a grimy old flush pipe. For some reason the previous owner tried to paint it, resulting in a flakey disgusting and unsightly eye sore. I have never done any type of plumbing and have manage to change both flush pipe and connector, with no leaks whatsoever.

[@dereton33]

That`s great Anne.

[@jgphotography3365]

This has helped so much. If I were to call out a plumber from my housing agency they will charge me way to much for replacing a rubber grommet for the pan. So I’m gonna pop down to my local plumbing shop and buy a new flush pipe and grommet.

[@dereton33]

Well done you can do it. Who needs plumbers anyway. Ha ha.

[@jgphotography3365]

@@dereton33 Exactly that, if you know how to do it, then do it ha ha

[@Wal48]

Excellent advice, you are great at explaining. We took your advice and it saved us A LOT of money. Can’t thank you enough for posting this!

[@dereton33]

No problem

[@minibandit]

Genius, I think you may have just saved me buying a £600 new fridge freezer! Your description exactly matches my situation, and with mine also a massive build up of ice (a blob 4 inches wide) where the water is unable to go down the blocked hole (which is now black and gooey from years of being blocked) and water on the base of the fridge every few weeks which then leaks down the front when i pull the lower 'salad' drawer out. Thumbs up good man

[@dereton33]

leon baines No problem Leon. Al.

[@chillmeister]

Thanks for this. I had a right bother with mine. Really old cistern, and toilet so close you need a thin seat in order that it stays upright. Ended up using the new cone washer, nut, and flushcone with the old pipe as the new one was tapered near the bend, seemed a fraction smaller, and it wasn’t liking it. Works a treat now. Top man. Hope you’re feeling better.

[@dereton33]

Thanks James.

[@engineerau49]

Thank you very much for your valuable advice. I follow it to replace my old cistern with Caroma plastic cistern. I get lazy and reuse the old pipe to the pan. Leaks keep come out from the pan after installation. I will cut a new pipe to replace the old pipe. Hopes the water leaks from the pan will stop.

[@dereton33]

Good luck with it 👍

[@Capstan05]

Such a breathtakingly simple and articulate manner, thank you so much.

[@dereton33]

You are so welcome!

[@ceedee9002]

Thank you, very clear and concise. Just one question, how do you know what length to cut the pipe leading in to the back of the toilet bowl? Just had to rep,ace a leaking seal tonight, and it definitely seems the plumber I had in to fit the loo originally did cut the pipe too short. I took a photo of the back of the bowl, and I can see three holes, main into the bowl, and one either side to take the flush around the rim, but where should the pipe fit up to inside the main inlet hole?

[@dereton33]

It should enter the back of the pan about two inches.

[@Joewalshe38]

Clear and simple with good tips, thanks. I am trying to fix the pan connection in a concealed cistern set up and after watching this I am thinking the pipes too short. Could be the cistern sagged over time from being full of water.

[@dereton33]

Joe Walshe Yes it can happen, a longer flush pipe is the only answer. Al.

[@Joewalshe38]

Thanks. Will post story when done

[@annavernick1490]

Thank you! I have an old system and wached your very clear video for the terminology, and what to buy for a replacement for my leaking flush pipe into pan. Cheers

[@dereton33]

No problem

[@billcarter3675]

Yes but do I have to shut the mains off before I commence changing the pipe? Am I meant to empty the cistern first??

[@kennymac6376]

im having a problem getting the plastic seal fully flush with the back of the toilet. I cant get it all the way home...its very tight fit. Any suggestions? Thanks again for a great video

[@dereton33]

Put some grease around the seal. Then push home.

[@alasdairduncan3]

Is there a specific sign that tells you the pipe is too short where it goes into the pan?

[@dereton33]

No afraid not. Just make sure it enters the pan an inch to two inches.

[@jabronirob45]

Mate, have to say your videos are actually brilliant and have helped me solve tons of problems - Just one quick question - I seem to have a 2" flush valve on my system which is leaking from the connection to the flush pipe but can't seem to find replacement sealing washers and nut for that size of pipe anywhere online, I'm stuck at my desk most of the day so it's hard to get to plumbers merchants before they close - Any recommendations for where I can get a decent one from? And once again brilliant work on the videos I'm sure you've saved countless people time and money!

[@dereton33]

Hi Robert, it can be difficult to find the washer for that size, you might be better off using some plumbers hemp and boss white around the joint. Just wind the hemp around then apply the boss white to the hemp, tighten the nut back up and it should be water tight.

[@MrPancakeRepairman]

Top vid Dereton33, really clearly explained. I've got a leak from the top part that you mention. It's in a hard to reach place behind a dodgy cabenit courtesy of previous occupant. I can reach it, but can't take it out without removing the whole unit. Is there anything I can use to seal the leak from below do you think? Many thanks

[@dereton33]

No it has to come out.

[@MrPancakeRepairman]

@@dereton33 Thanks mate I'll get it sorted.

[@mustafaabdullah5563]

Thank you for posting and giving knowledge to so many 🙏 😊

[@dereton33]

My pleasure!

[@brucewernick6542]

New cistern and new mechanism + flush pipe... 1. On the main outlet, is the rubber washer on the inside or outside? 2. When you install new cistern mechanism, do you use silicone on all the connections?

[@dereton33]

On the inside. No to silicone.

[@skaboosh]

Are the grommets into the pan all the same size? I have this problem... The pipe is also slightly angled so it's a bad installation from decades back.

[@dereton33]

They are.

[@johnmilner4146]

Thanks for the video. I have an old cast iron bell type cistern with a 35mm copper flush pipe, which I am keen to keep. I have renewed all the ball valve etc and it works fine but the new rubber bung to the new wc pan leaks. Can I get a bung specifically for 35mm copper pipe or should I use some sort of jointing tape or compound? Cheers

[@dereton33]

No you wont get one, Fill the gap with plumbers mait.

[@susananncarpenter4872]

Hi Al, great video. I have the leaking problem to showed. I am unable to find a shop or merchant that sells that plastic grommet for the back of the pan. Can you help? Thanks.

[@dereton33]

I am sure either Amazon or Screwfix do them.

[@richiesquest3283]

Great video what is the rubber seal called you fitted above the blue conical washer .

[@dereton33]

A flush pipe ring.

[@movementcoach7267]

Thank you very much for this, it sounds like mine is short then. I've spent the weekend fitting a new floor and refitting the toilet and it still laid so ill be off to buy a new pipe 👍

[@dereton33]

Great.

[@paddysmyth7768]

great video and thanks can you explain why my flush pipe is leaking before flushing? there seems to be a water supply constantly in the flush pipe. Is there a problem in the cistern?

[@dereton33]

The rubber seal between your cistern and the syphon is leaking, it normally just needs a tighten to stop it, if not remove the syphon and replace the rubber washer.

[@MrJohnyysmith]

Heres a novel cheap cure for a problem not mentioned. I replaced the flush mechanism today and got the surprise of my life. The connector blew off the back of the toilet and deposited a tank full of water on the floor. On examination I have no inner pipe seal and its 8 in the evening. My guess is that the new flush mechanism is dumping the water far quicker than the old one. The rubber outer seal is old but not cracked or perished. Cleaned that up and coated the mating surface with vaseline. Then used a long cable tie to hold it to the toilet. Seems to be working fine again and should be ok for another 30 or 40 years :)

[@dereton33]

Thanks for the info.

[@kenmannagh7788]

Love the t shirt and the helpful video , excellent 👌

[@stevecooper6515]

Might be a daft question but which way up should the conical washer go?

[@dereton33]

The thin part to the top into the syphon, the thicker wider part at the bottom.

[@addylinnett]

I need to shortern the flush pipe at the cistern end, will this effect the flush at all? Many thanks

[@dereton33]

No it will remain the same.

[@addylinnett]

dereton33 Thank You! 😁

[@reviewer3448]

How do I extend a flush pipe? As I have a very long flush pipe which I need to replace. Are there any adapter so I can interlock the piping easily?

[@dereton33]

There is no couplings for those. The only hope is a Macalpine 32 mm compression coupling.

[@dsslimone]

Thanks just found my built in wc has this problem. Good advice . Going to strip it down ill report back if I found anything else.

[@dereton33]

Good luck with it.

[@craigcope3369]

Hi, I have a client that needs this fixing for them if I buy a new pipe & bung how much should I charge? Many thanks

[@dereton33]

around £40.00.

[@craigcope3369]

Thanks mate.

[@fredshead3956]

Hi Al can you tell me something, i ordered a 2" seal for the base of the cistern on the inside, and its about 3" ID, so i got anther one from somewhere else and its the same, where does the 2" bit come into it, i got a 1.5" one as well. not sure which one it is, hoping one will fit, but what does the 2" refer to if the washer is about 3" ? from Fred in essex.

[@dereton33]

Hi Fred it refers to the inside diameter..

[@fredshead3956]

@@dereton33 Well it says its 2", it is infact nearer 3", strange thanks

[@stiggyjiggler]

I have this problem at my house, but the flush pipe is not PVC, it is a large cast iron pipe. How can I fix it?

[@dereton33]

+Crash Maverick . You can still fit a rubber or plastic insert on the end of the pipe and push it back into your pan spigot.

[@andysorsby76]

Thanks for the video! quick question. I have just installed a new cistern. I have now noticed that I have a leak between the nut on the underside of the cistern and the syphon washer on the inside? Any advice? I have tried to seal with silicone, PTFE tape on the thread etc.. but still leaks. New washer inside maybe?

[@dereton33]

Definitely.

[@andysorsby76]

Thanks for the advice! In the end I stripped everything down, cleaned all the silicone off! This time positioned washer and syphon dead centre and a turn on the nut hand tight only ! I think the syphon was moving out of place when flushing ! Now no leaks, or silicone or tape!

[@kellyannrogers3859]

please help any tips on getting the rubber bung into the back of the toilet? I'm struggling 😭 TIA xxx

[@dereton33]

Some grease around it or lard.

[@kellyannrogers3859]

tried nothing worked. turned out the guy in the hardware shop sold me the wrong bung 🤷‍♀️🤦‍♀️

[@jenniferhonig7643]

What if my pipe has been glued in on both ends and am unable to loosen and remove it? It is leaking at the long pipe as yours under the cistern where it connects

[@dereton33]

Just undo that connection, wind plenty of PTFE tape around it , then redo back up.

[@americanlegendsracing3893]

Brilliant video. Informative and to the point. Many thanks for the tips

[@dereton33]

Glad it was helpful!

[@steenystuff1075]

Excellent. Thanks, Al. Exactly what I needed to know.

[@dereton33]

Glad it was helpful!

[@simonpoole1492]

How far into the pan do you push the pipe through the flush cone?

[@dereton33]

An inch.

[@eugenedudley7609]

Al, is the cistern pipe normally water-filled or empty before the toilet begins it's flush?

[@dereton33]

It will be empty.

[@eugenedudley7609]

+dereton33 Thanks Al.

[@Rayblondie]

Thank you again. It's makes us know about the details which we need.

[@dereton33]

No problem Tony.

[@derekbainbridge55]

Hi Al, I've got a problem with a high level cistern with a flush that is too powerful. It splashes up from the pan like a fountain and wets the floor around the pedestal. I've tried reducing the volume of water in the cistern but while that makes a short flush the force is still the same. Now I'm thinking of trying to reduce the rate of flow. Any suggestions?

[@dereton33]

Yes, there used to be a flow restrictor that you could fit into the back of the pan, don`t know if you can still get them, or a 22 mm plastic tank overflow fitting, fits exactly into the top of the flush pipe, that also works.

[@derekbainbridge55]

Well done Al, the 22mm fitting works perfectly and it was easy to fit. Thanks for your kindness in sharing your experience and expertise.

[@quartelli]

YOU sir, are awesome. Thank you so much for this. Problem sorted.

[@dereton33]

You're welcome!

[@bejiem]

Thank you for your wisdom,, you just helped me.

[@dereton33]

You are so welcome

[@vikramsinghrathore6693]

Please give links to purchase these parts too

[@dereton33]

Will do.

[@aharris9915]

Thanks mate, as others have said, to the point with proper advice. Nice one.

[@dereton33]

No problem

[@dereton33]

Thanks

[@ronprice6543]

Where do we find the parts to repair toilet? Our toilet will use the 90° pipe.

[@dereton33]

Amazon or plumbing shop.

[@andrewmcgeorge7820]

Been searching for ages Cheers

[@dereton33]

No problem.

[@SH-cu9rc]

Great instructor.

[@dereton33]

Thank you.

[@kennymac6376]

i cant get to fit probably because I need to disconnect the cistern first. Im trying to connect the seal to pan with pipe still connected to cistern. 🙂

[@dereton33]

Best to remove it from the cistern.

[@ziggestzig1]

Very helpful. Thanks a lot.

[@dereton33]

You're welcome!

[@garysvantubelife]

As always very helpful , thanks you for the advice fella.

[@dereton33]

No problem.

[@patrinamuzembo6262]

Very clear explanation thanks

[@dereton33]

You are welcome

[@mikemaman1]

Still leaks between the plastic seal and the pan. will try to silicon it.

[@desmondrabbitrandyyankana7285]

Good job buddy tks for the info

[@dereton33]

No problem 👍

[@richardfroud8970]

Great video👍

[@dereton33]

Thanks 👍

[@diyman-kf3rg]

Great advice there thanks for posting.

[@natashadavies9569]

Thank you for this video

[@dereton33]

No worries!

[@houlbt]

Top advice - thank you

[@dereton33]

You're welcome!

[@hecateswolf6007]

Really helpful thanks

[@dereton33]

No problem!

[@ShesThe1yup]

NONE of these videos tell me if I have to turn the tap off and empty the cistern to change it over so it doesn't spill first

[@dereton33]

No you do not have too. I guess that was very remice of me on that video.

[@siroyal2040]

Good advice thanks

[@dereton33]

No problem.

[@acestevens4323]

Thanks mate!

[@dereton33]

You're welcome!

[@nickadamgu]

Thanks

[@dereton33]

No problem and thanks very much.

[@tftfotofili]

Very informative thanks heaps :)

[@dereton33]

Glad it was helpful!

[@victoriaives393]

tx- very thankful

[@maomharb]

Thank you so much

[@dereton33]

No problem

[@d4dolphinify]

thank you, thank you

[@dereton33]

You are very welcome

[@JamalGonzales-z8c]

Thanks bro

[@dereton33]

No problem

[@tobyarn1]

Legend! Cheers

[@dereton33]

Thanks Toby.

[@DeanWuksta]

thanks, big help

[@dereton33]

No problem.

[@carbugnov1952]

That L pipe is too rigid especially in limited space, i prefer the flexible ones .

[@dereton33]

Rigid is best

[@flaskandsarnies]

Would have been better if you had fitted a toilet and shown the method rather than just describing it, but good tips none the less.

[@dereton33]

+flaskandsarnies . I have a video on my channel showing fitting of a flush pipe.

[@jonesypaddlearounddevon]

👍

[@dereton33]

Thanks.

[@andre-dx4yw]

those plastic internal flush cones are total shit get a rubber one

[@dereton33]

Rubbers always best.

[@gavco11]

thanks for your help

[@dereton33]

No problem.