Whats wrong here?

My first suggestion would be incorrect cam/valve timing, BUT, you tell us that the timing belt is "mounted correctly", so if it's not that then what? Valves not closing? rings not sealing? head gasket leaking? glow plugs?

Maybe do a leak down test, that should give you an idea as to where the compression is leaking.

 

I have changed the head gasket three times looking for the fault. I grinded valves against seats as you should and leak tested.
The equpiment i got for compression leak test through the glow plug hole only fits on cyl 1. The needle barely moves. I'd have to remove the injectors to get to read all of them. But i think they are all as bad.

I have tried to find any fault with the timing. But i just cant find anything.
The three marks on the belt are put on the three sprocket marks. As every youtube video tells me. The cam shaft cant be put wrong.


I have not tried starting-gas or pulling it with another car to get it going. Could this be worth trying?