escort mk2 temp gauge shows overheating

[gnilrac]

Hi,there!Thanks for viewing my problem.I have a 1980 escort mk2,automatic transmission.My problem is the engine overheats fairly quickly,and not even strenuous driving.The waterpump appears to be moving the coolant as I can see it moving when the radiator cap is off.There is a small hole in top of radiator,about,1mm ontop.Can that little hole cause it to overheat so quickly?Any advice would be appreciated.

[dirty hands]

yes a hole can
you cant have any air in a cooling system like that ..it is pressurised
have the radiator and cores checked

the thermostat must be open if water flows
and check the thermatic fans if fitted ....do kick in

[gnilrac]

Thanks 4 answer.I patched hole this morning,but noticed there's a oil smear from the head gasket,not major,so I suspect its broken there.Could that also be a cause?And when refuelling ,I can smell that the petrol somewhat fuming from the locked petrol cap!Its like the petrol is trying to leak out of the cap?What could that be,as I am dumbfounded with that one.There are no leaks ,fuel.oil or water visible wen I leave the car overnight with a clean cardboard underneath.Thanks again for advice.