My real car's engine temp

[Big G]

I drive a mk4 golf TDI and in the normal UK weather the engine temp sits just below the 90 degree mark on the gauge. The Mrs has exactly the same car, but her's has AC and mine doesn't and her's sits bang on the 90 mark.

Now the snow has arrived it's dropped to probably the 80 degree mark, but when I use the heats on level 3 the temp drops to probably 60 degrees. If I use the heaters on level 2 the temp goes back to around 80.

Is this normal or is my antifreeze a bit off? It's never frozen solid, but I haven't ever changed my coolant since owning the car lol. I've had it for almost 3 years now. I'll get it checked anyway and replace it needed.

[smokes]

diesel always run cooler than petrol any hotter than 80 degrees will eventually cause the head to warp or lead to gasket failures. You could always put some cardboard in front of the radiuator like london taxi cab drivers do in the winter. not reccomended though. If you didn't have any anti freeze you would have siezed the water pump or cracked the block.

If the temperature is dropping it is probably cause there is snow between the bonnet and the windscreen. Which is where the air intake is for fresh air to the interior. but you should top up the coolant once a year as the gylcol(anti freeze) will evaporate off over time.

[Stu]

Originally Posted by smokes

diesel always run cooler than petrol any hotter than 80 degrees will eventually cause the head to warp or lead to gasket failures. You could always put some cardboard in front of the radiuator like london taxi cab drivers do in the winter. not reccomended though. If you didn't have any anti freeze you would have siezed the water pump or cracked the block.

If the temperature is dropping it is probably cause there is snow between the bonnet and the windscreen. Which is where the air intake is for fresh air to the interior. but you should top up the coolant once a year as the gylcol(anti freeze) will evaporate off over time.

??????? - LOL.

[smokes]

Err so your saying combustion chamber temp is the same as coolant temp? Which it isn't btw. And driving for 4 miles without coolant isn't going to warp cylinder head.

Warping is cause by uneven Thermal load across the head....

I may have said the wrong temperature cause I was trying to be simples 80 for the old indirect injected pug engines 87 for tdi with 5 phase injection, yes I know about knock sensors to allow you to run the engines as lean a possible. All I was saying was saying it a not a good idea to let it run hot.... And I said eventually AND not immediately!!

And are you sure there isn't a damping algorythm on the ford gauges at all? I am sure there is.

[mark christopher]

Originally Posted by smokes

Err so your saying combustion chamber temp is the same as coolant temp? Which it isn't btw. And driving for 4 miles without coolant isn't going to warp cylinder head.

Warping is cause by uneven Thermal load across the head....

I may have said the wrong temperature cause I was trying to be simples 80 for the old indirect injected pug engines 87 for tdi with 5 phase injection, yes I know about knock sensors to allow you to run the engines as lean a possible. All I was saying was saying it a not a good idea to let it run hot.... And I said eventually AND not immediately!!

And are you sure there isn't a damping algorythm on the ford gauges at all? I am sure there is.

oh dear you have done it again.
i have never claimed combustion temp is same as coolant, combustion temp is far greater than the coolant, but as your the bofin you would im sure know why its called coolant!
what sort of dick head rekons drivin for 4 miles is not going to warp a head? ,if thats your advice, keep ur gob shut! if the coolant has gone and the engine is a normal operating temp, then driving 4 miles stands a very high chance of doing damage to the head
why quote temps for an old pug engine when the posters question was about a modern VW? you back pedaling?

finaly ur next gaff
leaning (which is reducing the amount of injected fuel) a diesel simply reduces the throttle, richening (adding more fuel) increases power. from idle to full speed you add more fuel during the injection phase.
modern engies use the multi injector phase to get a more efficient burn which reduces knock, emisions and better mpg.
if you dont run your engine hot you get more wear and less mpg!!!

[SlowOne]

Originally Posted by smokes

For the gas turbines I know jet engines pump the Jet fuel into the blade to cool them and heat the fuel up before being passed to the fuel injectors, or what I call a very large tap... Which they use silly putty and diamond shards/dust to polish. Also the blades are single crystal but this so they can cope with creep. Theres a bunch of other aerodynamic tricks they also use for cooling but i don't have the knowledge on that.

Or on anything else it seems!! That's all rubbish, and should be ignored.

Originally Posted by smokes

my keyboard is fecked missius spilt water on it so i= iu every time a press it.

That's not the only thing that's fecked in your house - the bit between your ears seems to be suffering from a faulty thermostat as well!!

Do us a favour, break your keyboard into little bits and send it to the re-cyclers!!

[Nightshade]

Although it's best to change anti freeze every once in a while, in practise most people don't. Modern stuff will go a very long time without loosing it's ability to stay unfrozen, so I wouldn't worry about it.
Besides a frozen cooling system wouldn't be affected by the level your fans on.
But remember that the more hot air you ask the car for, the more heat you're displacing from the engine into the cab. A cool engine is a happy engine (with the exception of when you're trying to start a diesel). So don't panic unless it starts getting too hot.

I don't mean to burn you smokes but, please for god's sake don't put cardboard in front of the radiator!
The original idea was to block the cooling effect of the radiator and stop it reducing engine temperature before the engine had a chance to get warm - a secondary effect was to stop the coolant freezing if the wind chill factor exceeded the antifreezes freezing point. A principle that was completely obsolete by 1930 with the invention of the thermostat and the advances in antifreeze technology by about 1940. So unless you've got 1940's antifreeze in a 1930's car, it's pointless and more likely to make the engine run hot!
I see people doing it and I want to shake them!

[mark christopher]

Originally Posted by smokes

diesel always run cooler than petrol any hotter than 80 degrees will eventually cause the head to warp or lead to gasket failures. You could always put some cardboard in front of the radiuator like london taxi cab drivers do in the winter. not reccomended though. If you didn't have any anti freeze you would have siezed the water pump or cracked the block.

If the temperature is dropping it is probably cause there is snow between the bonnet and the windscreen. Which is where the air intake is for fresh air to the interior. but you should top up the coolant once a year as the gylcol(anti freeze) will evaporate off over time.

lol fell off my chair laughing at that..... friggin arm chair mechanics!

engines will safley run above 100 deg C without damage or boiling, as your an expert ill let you figure out how they dont boil over when the coolant temp is over 100deg c

[mark christopher]

Originally Posted by Big G

I drive a mk4 golf TDI and in the normal UK weather the engine temp sits just below the 90 degree mark on the gauge. The Mrs has exactly the same car, but her's has AC and mine doesn't and her's sits bang on the 90 mark.

Now the snow has arrived it's dropped to probably the 80 degree mark, but when I use the heats on level 3 the temp drops to probably 60 degrees. If I use the heaters on level 2 the temp goes back to around 80.

Is this normal or is my antifreeze a bit off? It's never frozen solid, but I haven't ever changed my coolant since owning the car lol. I've had it for almost 3 years now. I'll get it checked anyway and replace it needed.

i would look at getting a new thermostat fitted, mates passat with same engine suffered the same as yours, the stats get weak and open early or stick open preventing the engine from getting to norm temp, when you call on more heat from the heater the engine is cooled and carnt build up temp.

[Big G]

yeah I think I might since they're cheap and easy to replace.

Coolant doesn't boil at 100 because it's boiling point is higher than water? plus it's in a airtight system? also not sure how my antifreeze can evaporate when locked into an airtight system, but hey. I don't have all the answers since I'm asking for advice

[smokes]

I was trying to keep it simples......

I Design much more complex pressurised systems than car engines. Yes I know you can run them to a 100 degrees c but I wouldn't recommend it.

[mark christopher]

Originally Posted by smokes

I was trying to keep it simples......

I Design much more complex pressurised systems than car engines. Yes I know you can run them to a 100 degrees c but I wouldn't recommend it.

you may do but (but do you understand em?) i work on "basic" car cooling systems and have done for 25 plus years
you best tell ford and many other manufactures they have got it wrong as cooling fans dont come on till around 100deg and your claiming no more than 80!! (on what grounds??) its total bolox that the head will warp or the gaskets will fail at 100. most thermostats open at 80 to 92 deg c, tad more than you recomend!

simple is often danjerous as running engines too cold causes wear and uses more fuel!

[mark christopher]

Originally Posted by Big G

yeah I think I might since they're cheap and easy to replace.

Coolant doesn't boil at 100 because it's boiling point is higher than water? plus it's in a airtight system? also not sure how my antifreeze can evaporate when locked into an airtight system, but hey. I don't have all the answers since I'm asking for advice

yup mate did his and was easy job, coolant does not actually stop boiling its an antifreeze and lubricant/rust inhibitor.
the presure lowers the boiling point of the coolant, same as a pressure cooker thats why if u have a hot engine and you take the cap off it boils out

[Aaran]

most thermo's open at 70-85c (i have the qh thermo book which lists them all , average is around 72/3c )

and yes its a common as muck vw golf mk4 fault with the thermos opening to early, they jsut go sloppy and dont shut fully, shove a new one in and all is done. also the coolant temp sensor can start to fail which can cause the needle to read low (will either be a 2 pin green or 3 pin blue plug on the top rad hose) jsut change them both when the system is empty of antifreeze

had your windows fallen out yet? got to love that fault to! (most reliable car i have ever owned in my life, not lol)

[Big G]

it's falling out in this car yes, but it was before I owned it lol

The window in the skoda at work just fell out lol. the Mrs pushed down on hers when it was frozen and it stayed up and the mech went down lol

[mark christopher]

Originally Posted by Aaran

most thermo's open at 70-85c (i have the qh thermo book which lists them all , average is around 72/3c )

and yes its a common as muck vw golf mk4 fault with the thermos opening to early, they jsut go sloppy and dont shut fully, shove a new one in and all is done. also the coolant temp sensor can start to fail which can cause the needle to read low (will either be a 2 pin green or 3 pin blue plug on the top rad hose) jsut change them both when the system is empty of antifreeze

had your windows fallen out yet? got to love that fault to! (most reliable car i have ever owned in my life, not lol)

id buy a new book then, they aint been that low for years, all modern cars run hotter to help emmisions, take a look below not one below 80 deg

http://auto.howstuffworks.com/question248.htm

http://autos.yahoo.com/maintain/repa...ques018_2.html

http://www.ehow.com/how-does_4895412...tats-work.html

http://www.ehow.com/how_2189728_test...hermostat.html

http://www.helium.com/items/1766866-...rmostat?page=2

this is more relevent to the car
http://www.eurocarparts.com/ecp/c/Vo...bada3a48c&TSTA

oooo look 87deg




Thermostat
The thermostat is simply a valve that measures the temperature of the coolant and, if it is hot enough, opens to allow the coolant to flow through the radiator. If the coolant is not hot enough, the flow to the radiator is blocked and fluid is directed to a bypass system that allows the coolant to return directly back to the engine. The bypass system allows the coolant to keep moving through the engine to balance the temperature and avoid hot spots. Because flow to the radiator is blocked, the engine will reach operating temperature sooner and, on a cold day, will allow the heater to begin supplying hot air to the interior more quickly.
Since the 1970s, thermostats have been calibrated to keep the temperature of the coolant above 192 to 195 degrees. Prior to that, 180 degree thermostats were the norm. It was found that if the engine is allowed to run at these hotter temperatures, emissions are reduced, moisture condensation inside the engine is quickly burned off extending engine life, and combustion is more complete which improves fuel economy.
The heart of a thermostat is a sealed copper cup that contains wax and a metal pellet. As the thermostat heats up, the hot wax expands, pushing a piston against spring pressure to open the valve and allow coolant to circulate.
The thermostat is usually located in the front, top part of the engine in a water outlet housing that also serves as the connection point for the upper radiator hose. The thermostat housing attaches to the engine, usually with two bolts and a gasket to seal it against leaks. The gasket is usually made of a heavy paper or a rubber O ring is used. In some applications, there is no gasket or rubber seal. Instead, a thin bead of special silicone sealer is squeezed from a tube to form a seal.
There is a mistaken belief by some people that if they remove the thermostat, they will be able to solve hard to find overheating problems. This couldn't be further from the truth. Removing the thermostat will allow uncontrolled circulation of the coolant throughout the system. It is possible for the coolant to move so fast, that it will not be properly cooled as it races through the radiator, so the engine can run even hotter than before under certain conditions. Other times, the engine will never reach its operating temperature. On computer controlled vehicles, the computer monitors engine temperatures and regulates fuel usage based on that temperature. If the engine never reaches operating temperatures, fuel economy and performance will suffer considerably.

[showtime]

Originally Posted by mark christopher

yup mate did his and was easy job, coolant does not actually stop boiling its an antifreeze and lubricant/rust inhibitor.
the presure lowers the boiling point of the coolant, same as a pressure cooker thats why if u have a hot engine and you take the cap off it boils out

i'm sure you meant that the pressure in the cooling system raises the boiling point of the coolant

just pointing it out

[mark christopher]

Originally Posted by showtime

i'm sure you meant that the pressure in the cooling system raises the boiling point of the coolant

just pointing it out

yup well spotted been a long day......

[Stu]

Originally Posted by Big G

I drive a mk4 golf TDI and in the normal UK weather the engine temp sits just below the 90 degree mark on the gauge. The Mrs has exactly the same car, but her's has AC and mine doesn't and her's sits bang on the 90 mark.

Now the snow has arrived it's dropped to probably the 80 degree mark, but when I use the heats on level 3 the temp drops to probably 60 degrees. If I use the heaters on level 2 the temp goes back to around 80.

Is this normal or is my antifreeze a bit off? It's never frozen solid, but I haven't ever changed my coolant since owning the car lol. I've had it for almost 3 years now. I'll get it checked anyway and replace it needed.

G, my bus (the DogMilk van) is just the same as yours. In summer it runs normal temp. In winter when I have the heater full-chat it runs cooler when driving round town. I assume this is due to the engine been super efficient on fuel and threfore does not generate much internal heat, especially when it's below 1500rpm. The heater is very good, I assume it has a large matrix that takes much of the heat out the system, so the engine runs cool. When I turn the 'blower' off the temp goes back up.

As soon as I start using throttle or revs on the motorway or such the temp goes back to normal.

Stu.

[Stu]

Smokes, I'm a home garage mechanic and I know heads don't warp 'till they are very very hot, over 100c.