Hi I am new to the Forum, My 899cc seicento runs fine with the heater blower on, If I switch it off the car overheats. The raditor feels cool even when the car overheats. I have tried a rad flush and bled the system several times. The top hose is getting hot so I presume the thermostat is opening Do you think a new rad will cure the problem. Any help greatly appreciated.

Take the rad off and flush it backwards using a hose. That will soon tell you whether it is blocked, and may even free the blockage.

Cheers

SPD