Engine becomes hot.

Depends on what kind of heads you talk about.

how to?
open hood(bonnet) and remove the latch (screws)
replace it
the adjust it . per FSM book.
if you cant open it , that is a problem. so, if the latch is cable driven
most cars we can pull side of cable (look all places for it)
do this
person one tries to lift hood
person 2 tries to pull cable.
person 3 pulls cab handle, POP!
ok its not cable driven its electric
hot wire the solenoid. find the wire to it and hot wire it.
we have to Australia cars here so our alldata.com is of no help.

sorry would need my head nder the bonnet to know the cause ,if Ac works whilst driving then suspect a fan not coming on or a piece of plastic in front of the rads ,but this is outragous but yes i have seen this ,and dead flies and bugs blocking a rad but i would really need to see a vehicle with this sort of problem to know the cause

You should check the coolant is actually travelling around also the condition of the coolant and when cool check the radiator

the water pump is at the rear of the engine rh has you look under the bonnet and is driven by a belt from the rear of the b bank exhaust camshaft,

It sounds like the temp sender may be bad. This is the sensor that sends a signal to the gauge on the dash (as opposed to the engine coolant temperature (ECT) sensor that goes to the ECU instead.) It is located on the bottom front of the thermostat housing (which you will find if you follow the large hose from the top right of the radiator.)

Before replacing, make sure the connection is clean and secure, then check the wiring for any obvious failures.

If it won't start now, you would need to check for spark to the plugs and fuel pressure along with trouble codes in the computer.
You'll need to know what direction to go in to proceed.
It's possible the computer shut down the engine if it was too hot, but your temp gauge should have reflected that.

You did not say anything about the fuel system. Have you checked the fuel pressure ? Has the fuel filter been replaced this year ?
Is the check engine light on when the engine is running ?
Could be low fuel pressure or a faulty throttle position sensor among other things.

First thing to check would be the water pump. With the engine off, look under the hood and grab the fan with both hands. (Some cars have two fans, an electric one, and a belt driven one.) You want to grab the belt driven fan, and see if there is any play. Also check the coolant level, then check for leaks at the water pump. Make sure all belts are in place. This is the place to start, if the water pump is good, it could be a bad head gasket, you may have lost compression on one cylinder, causing the engine to run roughly.

Make sure the reservoir coolant tank is at 'full'. Start the car from cold and observe. After a couple of minutes when the engine has begun to drop in revs ( the coolant temperature sensor should tell the ECU to begin to shorten the injection cycle as the engine warms) the top of the engine and the coolant passage to the thermostat housing should become warm to the touch. When hot the top rubber hose to the radiator should become warm and then hot as coolant begins to circulate. If the top hose fails to get hot at any time then the thermostat is at fault. If you have electrically driven radiator fans these should now come on. If they fail to come an at all you need to check the coolant temperature sensor, the electrical motor fuses and the motor relay. Lastly check the motor itself (just run a 12v supply to it directly). As the ar continues to idle, with the fans running, the bottom return hose from the radiator to engine should also become warm. If the bottom hose fails to become warm this points to circulation problems. Either the radiator had become clogged with rust sludge and needs an extensive flushing out with a high pressure hose or the pump is not functioning as it should. Quickly check that the interior heater works by asking for 'full heat with fan on full'. If the interior heater works this indicates that the main coolant pump is probably OK. To check the thermostat more thoroughly, remove it from the car and drop it in a pan of near boiling water; the 'stat should pop open. As the pan cools, at 88 degree centigrade or so, the 'stat should pop closed. Failure to observe this tells you the 'stat is a dead and needs to be renewed.