UPVC to terracotta joins

[Compleat Repeat]

Plumbers all, I'm thinking of replacing a section of old terracotta sewerage line under the house. This section at its top end was laid integrated into the foundations on sandstone i.e. there is a course of brickwork and concrete slab laid on top of the terracotta line.
The terracotta line was laid with an incredibly hard mortar mix, both bottom (on the sandstone) and top (under the foundations brick course). It would be easy enough to cut it with a 9" grinder and break it out, but I don't see a way of cleaning the hard mortar off the remaining terracotta pipe to get a PlumQik-type external sleeve join on (i.e. female PlumQik to male terracotta). Is there a reverse join (i.e. male UPVC to female terracotta) that can be waterproofed to work on this uphill end? What other alternatives exist? Could the mortar be removed - noting limited access on the far side - in some other way?
Cheers

[r3nov8or]

Anything you put inside the earthenware will only reduce its diameter further, and by modern standards it's small to start with, and so increasing the risk of blockages. But if there's no other option, maybe you could use some PVC pipe to fix in there, leaving enough exposed, and work a joint off that... Hopefully a plumber will be along soon

[droog]

As above you will reduce the internal diameter and create greater potential for blockages.

Best option is an external adaptor as you mentioned as it does not reduce the internals
https://www.fernco.com.au/product/adaptor-couplings

But if there is no option then there are these
https://www.fernco.com.au/product/ic...rnal-couplings


Not a plumber and have no personal experience, but sometimes there is no other way.

[r3nov8or]

Good find droog!

Hope there's one perfect for the pipe sizes needed here

[droog]

Good find droog!

Hope there's one perfect for the pipe sizes needed here

I did check that they are listed for use with 4" or 6" sewer to DWV, so unless OP has some weird non standard earthernware pipe.
https://www.fernco.com/internal-pushfit-couplings

Capture.jpg
https://www.fernco.com.au/assets/Upl...-V003MAY18.pdf

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https://hydroflowaus.com.au/download...heet-hmow6.pdf

[Compleat Repeat]

Gents, great find; these will certainly do the job. Nothing weird about my existing piping at all, so these fittings will work. Query sent to FernCo. I should have thought of them, they are the PlumQwik manufacturers.
My plumber will be pleased, because he was reluctant - reasonably - to undertake something that might well have gone to Major Cluster status pretty quickly!
Cheers