Cast iron to ABS Tub drain

Had plumbers remove old 2in cast iron p trap for a shower, and install a ABS 1.5in P trap for a tub/shower.
All he did was jackhammer around, snap cut the cast which broke all jagged at the lead coupler. He left about a lip ranging from .5in to 1 in protruding from the old Lead coupler. He then attached a Fernco type fitting with a metal sleeve onto the lip and then put in ABS P trap.

Now its all filled in, except a 9 x 12 box around it and I attached tub drain to test and it is leaking from the cast iron connection into the new Fernco sleeve connection.
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How do you fix this? Is there some sealant product that you can glob around the fitting??
geoff

p.s. this drain goes right into main stack

"How do you fix this"? Call the plumbers back that installed it!!

This is not a place for a gob-of-silicone-and-hope-for-the-best patch up. So when you call the guy back to fix it right, insist on a 2" shower drain. The 1-1/2" is minimal at best.

drain

All I can say is that from your description these were not "plumbers". A plumber would have know how to make a clean cut and a tight connection.

Yea, I have my doubts about this guy, hence the question how to fix. He is coming back in the am and I'll see what he says. I really dont want to have him re-jackhammer , get into the actual sewer line for fear of them breaking that line then its all a Ratf@&*!

wow. This is great. So he does come back, tries to tighten it. Still leaks. He says, "Well I'll just charge you for time and materials" and that now he needs to remove the old pipe out of the Lead filled coupler (he had a name for it) , then clean out the lead, then put in a new 2in piece and EPOXY it in. He says it will last for 30 years. I said "you caused the leak when you busted the pipe as you tried to snap cut it, why do I pay for more work?" . Never mind all that hassle which sounds like I will have to go to another plumber and pay even more $ to get it working now. And forget that now my entire bathroom remodel is stalled until this leak is fixed.
My question to the forum is, this idea of cleaning out the lead from this old coupler and using epoxy, is this an accepted practice in the plumbing biz??
ideas??
help??
geoff

I am also thinking....is it possible I could put a reducer fitting (fernco) ontop the old Lead Coupler? It seems to be in solid shape. Would the water get trapped? Probably would be a 3in to 1.5 reducer.
BTW, i pulled off the fitting around the broken stub and I think the issue is the edges are so crusty and jagged, the Fernco fitting just cant seal around it all. The bottom especially.
more ideas?
geoff