Low Temp Thermostat
Discussion
Look guys I am honestly not bothered where you buy your LTT thermostat but the various postings on this subject indicate that even very clever engineers do not understand how it works and why it is important to buy the right one.
The thermostat does not control the temperature it only controls the flow. It does not know what temperature the engine or coolant is running at - it is a device that a temperature "A" it is open "X", at temperature "B" it is open "Y" and at temperature "C" it is open "Z".
The result is how big the space is round the valve plate when it is open "A", "B" or "C" and the temperature of the engine and coolant that results is simply a function of the the speed the coolant circulates at when the thermostat is open at those positions and the ambient temperature (modified by whatever use the air-con is running at).
Relatively high flow can be achieved at high engine revs through a relatively small gap in the thermostat but as the revs fall nearer to cruising town speeds the flow drops considerably and the thermostat needs to have the right shaped hole plats and linear movement to stabilise the temperatures at these different flow rates and variations in ambient temperatures and the use or not of the air-con system..
What this means to those that don't understand is that just because a thermostat has a temperature number stamped on it - does NOT mean the engine will run at this temperature- it means that it may be somewhere close but may go up and down a bit from whatever set point it runs at as the engine is worked harder or less hard and other ambient conditions change.
To get all this right requires testing and we have carried out masses of testing before we selected the thermostat and setting we wanted and tested afterwards to ensure the results are exactly what we wanted.
I am not saying thermostats sold elsewhere are wrong in any way but just that they may not create the same outcome even if they have the same number stamped on them and as the dash board instrument lies - it may be difficult for customers who have fitted another thermostat to know if it is working right or not.
Thorough test results will be posted soon together with new products to improve cooling etc.
Baz
The thermostat does not control the temperature it only controls the flow. It does not know what temperature the engine or coolant is running at - it is a device that a temperature "A" it is open "X", at temperature "B" it is open "Y" and at temperature "C" it is open "Z".
The result is how big the space is round the valve plate when it is open "A", "B" or "C" and the temperature of the engine and coolant that results is simply a function of the the speed the coolant circulates at when the thermostat is open at those positions and the ambient temperature (modified by whatever use the air-con is running at).
Relatively high flow can be achieved at high engine revs through a relatively small gap in the thermostat but as the revs fall nearer to cruising town speeds the flow drops considerably and the thermostat needs to have the right shaped hole plats and linear movement to stabilise the temperatures at these different flow rates and variations in ambient temperatures and the use or not of the air-con system..
What this means to those that don't understand is that just because a thermostat has a temperature number stamped on it - does NOT mean the engine will run at this temperature- it means that it may be somewhere close but may go up and down a bit from whatever set point it runs at as the engine is worked harder or less hard and other ambient conditions change.
To get all this right requires testing and we have carried out masses of testing before we selected the thermostat and setting we wanted and tested afterwards to ensure the results are exactly what we wanted.
I am not saying thermostats sold elsewhere are wrong in any way but just that they may not create the same outcome even if they have the same number stamped on them and as the dash board instrument lies - it may be difficult for customers who have fitted another thermostat to know if it is working right or not.
Thorough test results will be posted soon together with new products to improve cooling etc.
Baz
There is quite a lot more to it than this but most "home mechanics" should be able to cope. We always road test any car brought in for work to ensure there is nothing else seriously wrong with it (in our experience) that will be imminent and more important to repair than the job it may be booked in for - so we can at least inform the owner before starting.
If we do it - we receive the car, empty the old coolant, obviously check around other parts of the system, supply and fit the new Hartech thermostat and gasket, re-fill with fresh coolant (effectively a coolant change), bleed the engine with the right "Porsche" tool, check fans and the system for leaks, road test the car, allow to cool, final level check and top up if necessary. Our charge for all this is £250 + Vat (including all parts and materials).
Sometimes (like a number of other similar components on the outside of the engine casing) the bolts will snap due to corrosion and lack of a corrosive inhibitor during the original specification and assembly - and if so there may be an extra charge to drill out and helicoil them.
Baz
If we do it - we receive the car, empty the old coolant, obviously check around other parts of the system, supply and fit the new Hartech thermostat and gasket, re-fill with fresh coolant (effectively a coolant change), bleed the engine with the right "Porsche" tool, check fans and the system for leaks, road test the car, allow to cool, final level check and top up if necessary. Our charge for all this is £250 + Vat (including all parts and materials).
Sometimes (like a number of other similar components on the outside of the engine casing) the bolts will snap due to corrosion and lack of a corrosive inhibitor during the original specification and assembly - and if so there may be an extra charge to drill out and helicoil them.
Baz
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