Tictictic...

WellsieTRD said:
Diesel cooling systems are more effective than petrol systems as diesels run hotter. Something to do with thermal conductivity
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Wtf? I thought diesels were cooler than petrol engines. I sure know in winter it takes a good half hour of driving for my car to be able to give me hot air.

Petrol cars take 5-10 minutes, even in winter.

I think it has something to do with the fact that diesel burns more efficiently, ie creates more energy and less heat when igniting.... yeah?
 
Diesels run hotter because compression (anywhere from 14:1 to 25:1) is much higher than petrols and to ensure everything put in is burnt. To cold and diesel knock occures.
 
Burning temperatures:

Burning temperature LPG 1925 ?Cel
Burning temperature petrol 1986 ? Cel
Burning temperature diesel 1948 ? Cel

Compression temperatures:

Petrol engine 600 ? Cel
Diesel engine 900 ? Cel


Exhaust temperatures:
Forced induction direct injection Diesel: 800?C
Naturally aspired Petrol engine: 1050?C.


So it depends, the Diesel has a higher engine temperature, the petrol engine a higher exhaust temperature, and most likely the ticking results from heat directing metal plates in the engine to protect the engine from the exhaust heat and the exhaust itself, because as soon as your engine block ticks you are in deep shit ;). Brakes tend to squeak and scream as soon as they are getting hot while being used properly (i.e. MUCH), you get that awesome burnt brake smell like the whole Nordschleife parking lot has (ask the ringmeet guys ;))


NooDle said:
I think it has something to do with the fact that diesel burns more efficiently, ie creates more energy and less heat when igniting.... yeah?
Click to expand...


Yes, way higher. As well, the engine block is way thicker because of the higher compression, so it takes even longer until it warms up, and the heat is directed to the indoor heating only when the engine is warm enough (a valve opens), so you freeze your ass off. That is why most modern diesels come with electric heaters to heat the cooling liquid and/or the air to the passenger room
 
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D-Fence said:
Burning temperatures:

Burning temperature LPG 1925 ?Cel
Burning temperature petrol 1986 ? Cel
Burning temperature diesel 1948 ? Cel

Compression temperatures:

Petrol engine 600 ? Cel
Diesel engine 900 ? Cel


Exhaust temperatures:
Forced induction direct injection Diesel: 800?C
Naturally aspired Petrol engine: 1050?C.


So it depends, the Diesel has a higher engine temperature, the petrol engine a higher exhaust temperature, and most likely the ticking results from heat directing metal plates in the engine to protect the engine from the exhaust heat and the exhaust itself, because as soon as your engine block ticks you are in deep shit ;). Brakes tend to squeak and scream as soon as they are getting hot while being used properly (i.e. MUCH), you get that awesome burnt brake smell like the whole Nordschleife parking lot has (ask the ringmeet guys ;))





Yes, way higher. As well, the engine block is way thicker because of the higher compression, so it takes even longer until it warms up, and the heat is directed to the indoor heating only when the engine is warm enough (a valve opens), so you freeze your ass off. That is why most modern diesels come with electric heaters to heat the cooling liquid and/or the air to the passenger room
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lol. We needed a German to reply to this with stats and temperatures and shit :lol:
Thanks!
 
well since we?re being all german, here?s some more germanness: :lol:

because of the higher compression ratios, and the slightly more "chaotic" (for lack of a better word) combustion due to the diesel self-igniting, diesel engines usually have cast iron crank cases rather than aluminium, which doesn?t conduct heat away into the surroundings as well as petrol engines...

also, the ticking comes mainly from the exhaust, my mini ticks a lot more now that it has a stainless steel exhaust system... :D
 
One day my exhaust was making sparks on the highway (we were really hammering that day), but no ticks after :-o
 
Could be because modern petrols are mostly all aluminium while diesel engines still are iron because of the high compression ratio. Aluminium expands far more with heat so it will tic more.

[edit]Hmm, didn't notice that the thread had a second page allready. [/edit]
 
DarkReaper said:
Could be because modern petrols are mostly all aluminium [/edit]
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:mad: Iron block aluminum heads, mister german. Unless 1995 isnt modern enough for you.
 
doesn?t really matter what specific combination of iron, aluminium, or other metals you use, diesels blocks will generally be heavier due to the bigger loads on the crankshaft...
 
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