help needed - blocked waste pipe

[Mike.S]

I have a blocked sink waste pipe and having failed with attempts to unblock it using a plunger and 'One Shot' chemical cleaner, fear I need to take apart the pipes.

Here's the offending pipes, pictured from under the corner kitchen unit:

The l/h pipe comes from the sink and the r/h pipe is from the washing machine and tumble dryer. What isn't clear is that the l/h pipe continues onwards through the wall where, after a 90 degree turn it joins the main Soil pipe.

Here's a pic from the outside:

Unfortunately, except for that joint of unknown type under the unit all other joints are solvent weld which, I believe, cannot be taken apart. Also there are several joints between the sink and the corner joint pictured which prevent me using a flexible rod to try to root out whatever's blocking it.

So, before I start cutting the pipe off at the outside wall (so I can physically pull out the blockage) does anyone know what type of joint that is in the corner? Can it be pulled/twisted apart and re-used? I didn't want to try without knowing, in case I make matters worse!

If I can't take that joint apart I assume the best approach is to cut off the pipe at the exit point then try to solvent weld on replacement pipe/90 degree joint, albeit there wont be much pipe length to join onto.

If it makes any difference, the o/d of the interior pipes is 44mm (40mm nominal?) and 56mm for the exterior pipes (50mm or 2" nominal, I assume) - fitted about 20 years ago and now blocked for the first time because we're about to exchange contracts on the sale :evil:

Any advice/thoughts would be welcome.

 

[Zeddedhed]

You could try one of these.

 

[clk230]

Worth trying caustic soda before taking anything apart

 

[Dusty]

I think you will find that the internal fitting is a 50mm solvent weld Tee , with two 50 to 40 reducers fitted to suit your internal pipe work , as a quick fix I would buy two 50mm compression couplers , go outside ad cut an 200 mm section out , leaving 50mm at the 90 bend . Use a garden hose to effectively jet back up the pipe and try and clear it , a metal coat hanger , cut and striaghtened out can be handy to work back up the pipe . When you have cleared the blockage , slide the compression fittings on to the stub and relocate and tighten . the couplers will have a ridge in the centre to help locate the pipe equally but for a few minutes work with a file you can file it out so you have slip couplings . Granted it is not ideal , but it will help you not having to replace it all .

cheers Sam

 

[Phil Pascoe]

Forgive my suggesting the obvious - you did block the overflow when plunging it? You can buy the pump type plungers that whack a load of air through the pipe - they're more efficient than the squeezy type ones.

 

[Flynnwood]

Before doing anything else, pour 4 or 5 kettles of boiling water down.

 

[Mike.S]

That was quick!

Thank you for the suggestions. That made by Sam/Dusty seems a likely solution.

Zeddedhed - thanks, I've seen those but having tried (hard!) with an electrician's flexible metal tape (for threading electrical cables) it seems the various right-angle and offset joints between the sink trap and the blockage will prevent that working.

clk230 - have tried various chemicals but I'm not sure they're able to reach the blockage (see above). I've even tried pouring from both ends and no joy

phil - thank you, the obvious often gets overlooked (drilling in reverse... ), but I actually had my son blocking the washing machine pipe, SWMBO blocking the main sink waste and overflow whilst I plunged the smaller sink alongside (it's a'bowl and half' sink) :!:

Sam/Dusty - your description makes sense but does mean I'm not getting easy access via that joint. I like the idea of cutting a section from the outside pipe and using couplers or compression joints to fix it - after a good rodding around. I'm fairly sure the blockage is just inside the wall - where the washing machine pipe (clogged with detergent residue) meets the sink waste pipe (clogged with...uurghh).

Many thanks to all.

 

[clk230]

Honestly try a solution made up with some caustic soda forget all the other so called drain unblocking chemicals .
Good luck with whatever you try

 

[Phil Pascoe]

Years ago I had access to CO2 cylinders. I used to get a hose with a straight connection (with no regulator), stick it as far as it would go down the pipe and turn the gas on. Only knew it not to work once, when it blew the plumbing apart. It had to be redone then anyway, so nothing was lost.

 

[Dusty]

As an alternative , and if you have room , and can reach underneath would be to slice it just back from the tee , where you think there is a blockage , if you cant get a hacksaw blade to it , try a wire saw , you can get them for less than a fiver on E---Bay as below in the link . have a large baking tray and some towels to hand , and when cut , any goooo will drop in to the tray , when cleared , use the same coupler method to re-join . it may take two to tighten , unless you have long arms to reach both under .

https://www.google.co.uk/search?q=wire+ ... Y8P12UM%3A

 

[Chrispy]

Have you got a wet dry vacuum cleaner? Try suck it out some times filling with water helps with this.

 

[Water-Mark]

I'd cut it outside between the elbow and soil and rejoin afterwards.
bear in mind the one shot cleaner is a very powerful acid so gloves glasses and plenty of water.

 

[Sheffield Tony]

If it is a kitchen sink and could be blocked by fat, and hot water isn't reaching the spot, careful application of warm air to the outside of the affected pipe might just help in combination with plunging.

But +1 for caustic soda (sodium hydroxide) too.

 

[finish_that]

as above be very careful when cutting as all that nasty stuff is hanging around in the pipes waiting
to get on your hands or in your eyes - rinse as much as possible - wear goggles and rubber gloves

 

[dickm]

When you've got it clear, if at all possible, fit access elbows on those right angle bends. It's almost bound to block again with the current layout.

 

[Mike.S]

With nothing else to do on this Saturday night I thought I'd 1) make a shopping list for tomorrow, including a) Caustic Soda b) One Shot c) various 50mm couplers and 2) remove the kick board from under the sink, realising I couldn't otherwise reach the pipe in the corner under the unit.

And this is what I found:

All those years of SWMBO accusing me of stealing her brushes (partly true) etc and there they are :lol:

 

[Steve Maskery]

Blimey, no wonder the pipe was blocked with that lot shoved down it!


S

 

[Phil Pascoe]

Grasp the nettle and replumb it? It might be the quickest and easiest way.

 

[thick_mike]

Definitely do the following before cutting...

1) wear eye protection and gloves. If you have used caustic solution it is far more corrosive than acids.
2) suck out water/chemicals
3) use a hairdryer/hot air gun to heat the pipe where you think the blockage is. Pour down boiling water
4) use the plunger

Most likely cause involves fat...if you can melt it, you have a good chance of unblocking the pipes without cutting anything.

 

[griggs]

Is the washing machine leg draining away OK?

Have you removed the sink trap to be sure it's not just the trap blocked?