1990 2.5 TDI 19J heater problems

Hi, this is my first visit to the Forum so be patient with me. My 2.5 TD 19j heater will not get hot. I have fitted a new Thermostat & rad cap. The thermostat housing gets warm but the inlet & outlet pipes to heater remain cold. Tried bleeding etc. Removing the heater pipes & running the engine does not do much. I expected water to pump out from at least 1 pipe but nothing but a dribble. Fan belt is OK & fan turns OK. Anybody any ideas?

Either it's a TDi or it's a 19J it can't be both.

Must be a 2.5 TD 19J

Thermostat stuck?? or waterpump fecked.

If it's a TDI it'll have a intercooler next to the rad.

New thermostat fitted. Fan turns as expected.

Sussed it, took both of the heater pipes off & flushed them out with the garden hose. Huge amount of rust & debris came out. Keeping the garden hose flowing through the heater pipes I refitted the first 1 then the other. Heater is now toasty. Must have been either an air lock or blockage in the pipes:clap2: