Hi, i just replaced the thermostat in my 300tdi.
I have noticed that the old one when fitted and cold reached all the way to the back of the housing and just touching the inlet or outlet hole whichever it is, but the new one is about 20mm short of the hole.
I thought it should be a lot closer than that but i purchased it at a landrover place so it must be right.
Obviously the old one is stuffed and was always almost closed (not good). Does anyone know how far they open up or expand when at temperature as i dont want to pull it out to test it.