Attempt #2 At Understanding Something (Excuse My Tiny Brain)

[WaterTight]

Job: Replace pictured cistern

Green arrow shows were metal flush pipe has a flange under the nut. Not just just a straight bit of pipe. This was sealed to old metal syphon thread with hemp. The whole assembly is old, gunked and has been heavily painted.

If I were to attempt to put new plastic syphon thread onto flange and use existing nut what should I use to make the seal?

If it won't play ball or I have allignment issues - given the very forward position of the flush pipe on the base of existing cistern, I have felt it might be best to cut the 1 1/2" metal pipe where the red arrow is and pipe back up to the new cistern (reason for cutting there is that where the flush pipe disappears out of shot down to the pan it disappears half into the wall and I'd rather not disturb it by attempting to change piping all the way down the pan)

If I need to do this (cut pipe where red arrow is and pipe up to new cistern) what should I use?

I'm thinking I could hacksaw the pipe, use an 1 1/2" McAlpine multifit compression couple, then pipe up to just below the cistern in 1 1/2" plastic (using fittings to get right allignment.) Would this make sense? And if so what would I then use to join onto the cistern. Would another 1 1/2" multifit jion 1 1/2" plastic to a standard flush pipe?

Thanks

 

[stevetheplumber]

going to look a bit naf with macalpines on it why not use a inch and a half swivel/loose nut coupling onto the syphon reduce to 1inch and a quarterrun it new in plastic

 

[pakmei]

or for the sake of a few quid replace the syphon and start again

 

[WaterTight]

going to look a bit naf with macalpines on it why not use a inch and a half swivel/loose nut coupling onto the syphon reduce to 1inch and a quarterrun it new in plastic

The only reason is because the flush pipe goes into the wall then comes out further down into the pan. It's all very a bit odd and inaccessible (put in a tiny space) and I explained I might have to use some unattractive fittings on it and he said he didn't care.

But if I understand you are you saying you can put 1 1/4" plastic pipe straight into syphon and get a seal as long as it has an "inch and a half swivel/loose nut coupling?" As in - don't use a standard flush pipe at all?

 

[Guest123]

Watertight, is there any particular reason why the cistern has to be a high level one? Is it purely for aesthetics, i.e not tiled behind the cistern? The reason that I ask is that this could easily be changed for a new modern low level plastic cistern costing about £30 and it then gives you more options to connect and make the flush pipe look better. you could hang a new cistern at whatever level looks the best. At low level, the cistern is easier to maintain (no ladder needed).

 

[WaterTight]

Well, I've already bought a Dudley tri-shell high-level (recommendation off here - seems really quality bit of kit) and yeah it's not tiled behind cistern. But I don't really see why doing a low-level would give me more options to connect? Surely just same set-up but a bit lower - still need potentially to re-jig flush pipe without being able to remove length going into pan.

How about using a 1.5" bsp trap connector to solvent weld to connect to syphon tail and then running in 1.5" plastic up to red arrow position with a multifit coupler? That might look marginally neater?

 

[Guest123]

My thoughts were that if the cistern was a lot lower, then you'd see a lot less of the flush pipe, but you've already bought a new cistern so this is out.

Yes your idea will work and a single multifit connector will look fine. Dudleys are good quality.

 

[WaterTight]

Cheers system.

Just a thought though - would a low level not risk a poorer flush where a high level had been installed before? I know the difference in distance is hardly much just didn't know if pans had been designed only to received a high level flush.

 

[dontknowitall]

"Oh, I'm sorry but I've got to dash - someone's just phoned about a stop tap they can't turn off and their kitchen's flooding ..."

 

[jase158]

Hi water tight, I have put mcalpines from plastic to metal before with no issues, as long as both pipes are 40mm
sometimes you can worry too much about things, just give it a go, perhaps get a few fittings and take the un needed ones back, you may do it one way and suddenly realise half way through that it would look better with the other fittings instead

 

[stevetheplumber]

the fitting in the picture is the one you want but the flush pipe only needs to be 1 1/4 to fit in the flush plug in back of pan so reduce it then no neeed to use any existing
or use that fitting ,short of pipe, then macalpine onto existing

 

[turnpin]

Hello tiny brain oops sorry Watertight dont be shy with this metal pipe scrape off the paint and using some gentle heat maybe a hot air gun and a wire brush clean it up and whilst it is still hot have a go at undoing the flush pipe nut perservere and I reckon it will go once removed give it a final clean and check the threads are ok make sure it has cooled down though I would seal it with a grommet made out of ptfe to sit on the lip of the flush pipe connector best of luck regards turnpin