Space between water line tile and coping.

[Ujustswim]

Looking for advice
This pool is a 30*50. 3' to 9' deep. It has 4 badly cracked skimmers that need replaced. There is a very uneven gap between water line tile and coping averaging about 2 in. It looks like the wrong material was previously used
From thePoolMath looks water has gotten behind tile through the materials crack. This pool is in Connecticut we're freeze damage is a problem. Some of the coping stones are loose
The material underneath seems like mush. I'm looking for and appreciate any and all advice to rectify the situation the correct way. My initial thought is that all coping should be ripped up existing tile and material chipped off. Replace with new coping and tile. I would like to avoid the gap between the tile and a coping
Dose the tile sit on a self?

 

[ajw22]

One of the first things you need to identify is where your expansion joint is between your pool and deck. I think a lot of your cracking and cracked skimmers is due to lack of an expansion joint.

Expansion Joints and Coping - Further Reading

www.troublefreepool.com

The tile does not sit on shelf. The tile butts against the plaster. Will you be replastering the pool? Usally the tile is installed and then the plaster is applied to the bottom of the tile.