had heads shaved, replaced head gaskets( using correct torque order), replaced all gaskets, replaced thermostat. filled collant with help of skilled Euro mechanic. still over heating. checked oil, not over full, not mixed with coolant. checked coolant, clean and no oil. Problem: topped off fluid, and bled. drive it around about 5 minutes later it over heats and upper radiator hose along with hose that goes down to thermostat swelled up. I relieve pressure from rad cap and it gurgles fluid back into res. limp it home making sure it does not go into the red. checked all connections from hoses they are tight. re-try to fill radiator and bleed. same problem. ???? any solid ideas. can I force open my thermostat to see if this is problem? remember that I have just replaced head gaskets.

 

You can remove thermostat for testing, they are cheap ($10 or so).

Oil pressure OK?

Water pump? Belt route (very easy to miss)?

Radiator plugged (check for hot/cold areas across it - should be uniform temperature). If "stopz leekz" was ever used, most of it would settle to bottom or radiator and plug 50% or more of it.