Heating problem 300tdi

Having bought a disco and like driving it I thought I better fix the heater and cooling system. When I bought it I was told it overheated it was fixed temp but you could do 30miles at about 50mph. The heater wasn't working and had been bypassed. It started to overheat after about 2 miles so I thought I better try and fix it.
I reconnected the heater and found it to be leaking so I fixed this.
I then bled the system but it is still overheating and no heat in the cab!
Any ideas what to do next?

The over heating is directly linked to the lack of heating in the cab, the 300Tdi is a whooooore to bleed and is renowned for air locking the heater matrix.

There are tons of threads about bleeding the system, I saw a thread where a guy filled the system via the expansion tank and then using a PVC pipe with a threaded fitting on that was a foot long he then filled the thermostat housing to the top of the pipe and then run the engine, the weight of water pushing down above the system forced the air through the system.

Sure a guru will be along shortly to give you a better idea of how to do it

Thank you. I think I have followed the instructions for bleeding and it still is not working. Do u fill the expansion tank to the fill level or to the throat? As you say it seems air locked and I can't remove it.

300 tdi isnt prone to air lock if you remove bung on top of thermostat housing and fill expansion bottle till they are over flowing ,system should be full unless heater matrix has a blockage , or you have other issue thats meaning coolant leaking out or been blown out , heater blowing cold is often a sign of head gasket issue but can be many others, things to check when engines hot are the two heater pipes are they hot or none or just one , does top hose get hot is rad hot all over core

+1 Just done mine this way, started it up and a few minutes later warm air is blowing through the heater. I'd be looking at water pump for starters as mine had got plenty of gunk on the blades