Welcome to the forum.
What you have there is a pretty rough but serviceable Zodiac MkII Grand Raid, made of hypalon with their patented inter-communication valves. Damn fine boats. They still make them, but you'd be lucky to change out of £5k, and that's without an engine.
Chances are you need this tool. I take it you just used claw grips? That might have been an expensive mistake, but they might be salvageable. In the meantime, spray some penetrating oil on them such as PlusGas and wipe off any excess.
https://www.rib.net/forum/f50/servic...ves-46297.html
Chas in the link are still there so email them regards the tool and PDF instructions. They are a Zodiac dealer in the UK. If you can save the valve, it will need new rubber cap insert, rubber diaphragm and gasket for a proper leak free seal, and the small issue of threading it again. I think a replacement is base Z2107 and cap Z2108.
I see you have the aluminium floor to the side. Do you have the aluminium stringers too? They often go missing, but you need them to keep the floor rigid once it locks in place.
Anyway post up pictures as you progress. Any loose bits of hypalon, then now is the time to repair. You need 2-part hypalon glue (see Polymarine site) and temperature and humidity are critical, as is preparation.
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Sula
