Hi all my 2004 disco 2 petrol overheated the other day. Did a pressure test and found it leaking from the throttle body, fixed that and pressurised cooling system and as it lost pressure i could hear water being pushed into the inlet manifold. Looking for some ideas to what's happened and needs repairs. I'm guessing hg has failed.

 

Not that simple if you can hear it is usually external, spend 40.00 get some UV dye and a flashlight. Dump the dye in run the engine at idle, WATCH YOUR TEMP once it gets good a warm shut it down. Use the flashlight to look for leaks, you can check hours later that stuff really glows under UV in the dark.

It could be a valley pan gasket, intake hose on top of the manifold, or even an external head gasket leak.