Technical Exhaust problem

[AnthonyH]

The putty should be impervious to water.

When heated the putty should harden and completely seal the joint

That's interesting I've had putty in the past that dissolved, this isn't recently though, its probably 2-3 years ago so the exact compound I used is lost in time.

I have just generic firegum putty, the stuff below, so I'll deffo put some of that on then.

https://www.halfords.com/motoring/tools/garage-equipment/head-gasket-and-exhaust-repairs/holts-firegum-paste-150g-741520.html