yeah you defiantly should have checked and changed the water in it when you first got it. You'll be able to get a thermostat from any auto shop such as supercheap and repco

Well I haven't tried to remove the thermostat yet, reason being look what was in my radiator!!!! I drained it today, looks like its never been drained or flushed in the 35 years its been alive. Yikes. Runs like a champ now with proper coolant in it. Could this be the reason for all my previous engine troubles????

Still planning to put a fresh thermostat in to be safe once I can source the part. Anyone know where?

Cheers.

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Don't trust the gauge, do as said above and measure the actual coolant temperature before anything else.

Many cars will run with the temp gauge needle just off the C mark, as long as it's in the range it may not be a big deal. Find out what the actual temp is. I will tell you that my old 720 pickup never ran more then 1/4 hot even when it was 112 degrees out. Sometimes in the winter I would partially block the radiator as even with 190 degree thermostat it would just barley warm up and the heater would be weak.

Main thing you will notice is the choke possibly staying on and the gas milage will suffer. With water temps below 160 degrees it is possible to wear the engine prematurely.............again find out what the actual temp is.

Tom

Removing the thermostat is straightforward. Firstly, get a catch tray to catch the coolant. Then remove the top radiator hose where it attaches to the thermostat housing at the front of the cylinder head. Then undo the bolt on the thermo housing and prise it off. There will be a gasket between the thermo housing and the head that is stuck together with gasket cement so likely you will need to force it a bit. Once it is off you can then remove the thermostat.

As for the effects of running too cold you must remember that an internal combustion is a heat engine.Heat is energy.It is harnessed by the engine and converted into mechanical action. Too cold and you are wasting energy out the radiator. Wasted energy translates to wasted fuel.
The cooling system is to allow the engine components to survive within their physical limitations. You can build an internal combustion engine from ceramic parts and have no cooling system at all because the ceramic components will survive the high temperatures.Cast iron and alloy components won't.

Remember an alloy cylinder head is tempered to a certain hardness. If you overheat your engine then the temper/hardness will very likely be lost. That means your cylinder head is now akin to a block of cheese. You will find that the head bolts won't keep their tension. You will always be tightening them down. What is happening is the head is deforming.Just get a block of cheese and squeeze it , you will see what I mean.

Perhaps a bit more information than you wanted but it seems to me you are keen to learn.

Cheers

Thanks for the comments guys. I've never dealt with a thermostat before so I'll have to read up on how to take it off and test it as you said.

Just curious though, what are the negatives to having the car run too cold?

Good advice.

The only thing that I can add is that a standard A10 and A12 are notorious for taking a long time to heat up and they cool down quickly. So nearly all the A series I have owned do not usually go past 1/3 temp.

That type of temperature gauge you have is at best a mere indicator.

The best thind to do is to get it up to usual operating temperature without the radiator filler cap on an then place a thermometer into the coolant in the top of the radiator. See what reading you obtain and compare that with the gauge on the dashboard.

And whilst you are using the thermometer , take the thermostat out. Firstly, see if it closes at atmospheric temperature. It should . If not then it is stuck and time to replace it. If it closes then place it in a saucepan of water and slowly heat on the stove.Get your thermometer and see what happens .The thermostat should be marked as to the temperature it is rated at. Observe when it starts to open and when it fully opens . See what temperature it is at these points. It should be near the rated temperature.

I've been reading up on the Cooling System in the tech wiki. My temperature gauge has never gone past 1/4 way to H as long as I have owned it....EVER. Most of the time it sits about an 1/8 of the way to H.

Does this mean my engine is running too cold? What are the symptoms and does it cause poor engine performance?

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