Over heated,,day before had a blown heater hose,changed it,on way to work,over heated,the termostate was froze ,replaced it,still over heating?

I had a 91 GMC 4.3 do the same thing. Liked to froze to ***** one winter. Found I had a air bubble (air lock) in the engine block and heater. It was a bear to get out. Finally installed back flush kit in the heater hose between engine and heater. Took cap off flush kit, pour coolant in through outlet till coolant ran through back to radiator. Replaced cap and started engine. Repeated again. Heater works as good as new. It's using the same principle as priming a gas powered water pump.

did everything said to do put new heater core in and a new thermostat instill no heat

make sure the cooling fan is working properly behind the rad as if its not the motor will run hotter than it should.the no heat indicates you may have a plugged heater core,you don`t say if the heat was good before the motor replacement.if it was then you still have air in the cooling system that needs to be purged.its also possible the head gasket may have a problem so you should have a combustion chamber test done on the cooling system.there have been problems with the water pump impellers not pumping coolant properly,like the impeller slipping on the pump shaft or the impeller blades worn/damaged not pumping coolant properly.

i am looking for a copy of the owners manual for a 2005/6 fiat strada 1.2el bakkie as we have lost the manual and i have now bought the bakkie from my company and need to do repairs i.e. the heater box is broken as water is leaking inside the bakkie - i need to know do i replace the complete heater box or what and also how do i replace it

Check the vacuum diaphragm in the heater hose. It's a little metal valve with a hose going to it. When the heat is turned on the vacuum line opens the valve letting hot water pass through the heater core.

check the heater lines both should be hot
some heater cores have valves to stop heat and help ac work better

check hoses if both hot then it's the heater box that has a problem acuator and likely it is

If your heater core hoses are frozen you should immediately drain the coolant out of your radiator and engine and refill it with the proper mixture. Your lucky if your heater core lines are the only thing that froze, it could have popped a freeze plug or two out of the block. You could use a hair dryer or heat gun if you need to unfreeze it quickly.

Are you saying the engine does not get hot or that your heaters are not working..?
If it's the heaters, change the temp control on the dash to full heat, then trace the heater hoses under the hood from the firewall back to the motor. Hopefully this will locate the heater tap. Now if the tap is vacuum operated, start the motor and check if there is vacuum at the small hose connected to the tap. No vacuum is correct. Now change the heater control to cold and there should now be vacuum at that small hose. if vacuum is still not present, or if you have vacuum but it does not go away no matter where the heater control is placed, suspect the control in the dash.. If the vacuum operation is correct, suspect a blocked or damaged heater valve and replace it..

you have another leak that is why there is steam coming from under the hood ,and no heat is because there is no coolant left to heat check water pump or loose hose clamp on radiator thank for your question.

Sounds like you have a clogged heater core. Sometimes heater cores can be flushed, but more times than not, it has to be replaced. If you've replaced the thermostat and your lower radiator hose is always cold, chances are it is the heater core. Hope this helps! Have a great day!