bit of a read but its not that bad
driving to newton yesterday (40min drive) i got half way and noticed my temp had gone from the normal temp i have which sits on the bar under the word normal (when not giving it some stick) had gone to the letter "m" in normal, it was fairly warm/hot yesterday so i didnt think much of it coz i was sitting at 3grand on the cam most of the way, anywayz i got there and turned off, did what i went there to do and left after hours of age 3 games , after a couple a mins after i had left the temp went back to "m" fairly quickly but not quick enough to make me think twice, got the car home after 1hr drive in peak hour (temp didnt budge off "m") , turned the car off and it was making a hissing noise....... Hmmmmm, open the bonnet had a small inspection and couldnt see anything, looked at it today after not starting it sinse yesterday and no water.... hmmmm odd coz i always check, must be a head gasket..........pumped 6litres of water into it and it just dissapeared, bout 1min later started hearing water hitting the ground. looked around a bit and found the heater hose had a massive gash in it...... so my first thoughts after that were "s**t" "is my car fukt", after some inquires and inspection etc etc the car should be fine (there must have "just" and only just been enough water circulating for the water sender to register a temperature, i am also told that if no water at all the sender will tell you the car is cold (which makes sense at there is no water touching it) , anywayz morale of the story is, fellas please check the temps of the nice fords you drive on a hot day, if it moves just the slightest more than normal do a check, i got lucky but someone else may not.

had the same problem with a mates car. I was driving and the temp was nromal but it was making a bit of a sound and a bit gutless.

Got home and it stalled in the driveway. Realised that there was NO water in it at all.
When i cooled we put water in it and found there was a 4cm gash in a heater hose just before the heater tap. We fixed that and it was all fine..

We also did a service because the oil would have cooked.

Dont worry about it till it starts playing games. At worst ull be rebuilding or new motor.

where abouts are you in Adelaide?

paralowie, opposite end of adelaide to you

The temp sender will just measue air temp in the thermostat housing if no coolant present. Your xr6 should have a low coolant switch sender in the reservoir tank?

I would say being a heater hose and the amount of driving you have done, your alloy head will be warped and a head gasket failure may happen, if not already leaking in the cylinders.

You would have lost all your coolant when the temp first went up and stayed up. Heater hoses once split will dump almost all your coolant on the road except for about 4 litres.

yeah see thats the weird thing, the sensor never went red, its brand new, i checked it when i put it in about 3months ago...
air temp in the thermostat housing would never reach optimal water temp though surely....? i mean doesnt the temp sender go straight to cold on the cluster when there is no water present?

perhaps it took a while to dump all the water?? i dont know, can that be a possibility?

- i havent driven it sinse the heater hose split coz i cbf fixing it at the moment, but the head goes in for saloon car throating soon so i might have to have the straight edge put up against it :'(

the temperature sensor is just a thermocouple. It will measure the temperature of the environment around it. Whether it is coolant or air, doesn't matter. It will read high on the gauge when driving around with no coolant because it is measuring a very high air temp as the motor begins to heatup and cook.

hmmm, no offense in my opinion your wrong, from what i have been told on other ppl's experience it registers no temperature, air is just not as dense as water and wont transmit anywhere near the heat that water will while the engine is running, that why "most" cars run liquid cooling because water can dissipate heat better than air because its more dense...?, therefore wont register a temperature reading like water will covering the pickup sensor, go ahead prove me wrong run your car with no water heheheheh tell me what happens....
but i stand to be corrected

no, EL Fairmont is correct,
i was driving my mates AU and it dropped all of its coolant, and the gauge went into the red, and started beeping at me. just connected the hose, re-filled the water, and it was all good!
and we use thermocouples at work, and when we take the water off them, they still register the heat.

hmmmm, i would love some more opinions on this, but at the moment i have lots of ppl saying different things to me..........so how come my car went to half temp? i obviously had no water in it, shouldnt it have gone to max temp on the cluster basically?

-also what type of thermocouples do u use at your work, arent there lots of different types, ie, ones for testing currency/heat through water, air, metals etc? A thermocouple designed for picking up water temp due to the spark it puts out would not be very effective in picking up a air temp because it would not be testing the right "dense" material?
once again i stand corrected

I think the temprature of the air has alot to do with it.
I was on a country road travelling, might have been doing 160+.
Temp looked fine until I pulled into a servo and BANG
Lucky I was on gas, cut the engine before it went really went BANG.
Not water, heater hose split underneath....but I had a nice big hole in the rocket cover. Not too sure how its affected the engine but 2 years later everything seems ok........

Don't really like car yards and dealers after that.

Was it the short piece of heater hose under the manifold?
Mine busted whilst leaving large circular black marks on the road LMAO.
The warning light on mine came up though, and took around 10 mins to empty radiator.

at 160km/h i would assume that the air would be cold enough.... LOL maniac....
anywayz the thermocouple that ford used in the el whether it be different to other models or not would not possibly read hot air anywhere near as accurate as it measures the temp of water because a thermocouple uses small electro sparks/pulses to read, thick/thin/long and how long it takes to get from a to b in a certain dense material, basically this one has got to be mythbusted i am absolutely certain that if there was no water on the sensor at all it would read basically close to cold on the instrument cluster...... and after talking to some ppl that build engines for a living they are in agreeance, but there is always gonna be some instances with anomalies like some water still circulating like my case that makes it still read a temp or high temp....
once again again i might be wrong, although i doubt it with this much proof.......

I am right buddy!! my opinion anyway but i have seen this happen before!

that's why alot of people install low coolant alarm float switches in there reservoir tank in low series models.

I have seen it happen in a mates mum's AU falcon. She complained to him that the car had lost a s**t load of power and running hot. Well we took it for a drive, temp gauge went to 3/4-hot and the car went into engine safe mode( fires only a couple of cylinders at a time). popped the bonnet, no coolant in the reservoir tank, further inspection showed the back heater hose had split.

Replaced the hose, topped up with coolant (about 10l) and all was good. Good thing Au ford's have this engine safe device when overheating occurs.

well im sure in cases thats true, but everything i know about thermocouples and ppl like bruce heinrich who i have talked to, anywayz with everything i have talked about looked into a know, a thermocouple configured to work in water/coolant could not possibly give a reading on hot air anywhere near accurate, in fact if it did give a reading it would be very minute due to air or even really really hot air not being very dense, then causing the electrode in the thermocouple to give a complete false reading because its sparking too quickly/not long enough or being too thin of a spark in low friction circumstances, facts point towards a cold reading on air.... and so do ppl in the know.... i think we should do a mythbust on this

and also they only put a low coolant alarm in early models because they dont have one already resulting in not knowing if they have fluid loss, not because they wanna see if it gives a hot or cold reading when there is no water in car...... and yes the car will run hot if there is still some water in the car, you would have to lose the bottom radiator hose to lose all coolant?... so yes it will run very hot, but the point im making is if there is no water at all, there is a difference..

What we do is take a toasty oven to the car and a kettle.

Put the cluster in diagnostic mode and put the temp sender in the constanly boiling water. The cluster will tell us 98-104°C.

We then put the thing under the toasty over lamp and have another thermometer in there. We then compare the two readings and see how much they are out.

Just for physics sake (my teacher will not be proud of me if we didnt do this). We take the differences an we work out a percentage that they were out. If its more then +-%5 out we can say that it will not work for air temp it its within that bracket we can says that it is 'plausable'.

Who wants to test it?

Myth Busted.