Warm Up Time / Oil Temp - When is it ok to cut loose?

[dave_r]

Looking at the high end of engines, say F1, why are they are pre heated by circulating hot fluids prior to starting, then have a stationary warm up then a track warm up...go figure? Tradition, entertainment or engineering?

Hehe so a highly strung, pushed to the limit F1 engine has what exactly in common with a Golf engine?

Ultimately it's your car and you get to do what you please...

This is true but unless you keep cars for 10yrs, whats the point of being paranoid? After getting out of the garage and a around a few corners, drive it like you stole it. I always have, whether the cars made it to 5yrs old is another story but not my problem. I buy my cars for me to have fun, not the next bloke. But in saying that, if the servicing is done according to the required sheduled with hard/short driving then I don't see any harm being done.

interesting that out of 55 respondants 17 drive it hard without warming it up to 80deg (30%) statistically thats quite high....

Might be a bit misleading. I voted don't wait, don't care but living in a court and speedhumps in the next street, its probably a min or 2 before I get onto a road where I can start flogging it. Not looking at any temps though, so I guess it counts all the same.

[pologti18t]

This is true but unless you keep cars for 10yrs, whats the point of being paranoid? After getting out of the garage and a around a few corners, drive it like you stole it. I always have, whether the cars made it to 5yrs old is another story but not my problem. I buy my cars for me to have fun, not the next bloke. But in saying that, if the servicing is done according to the required sheduled with hard/short driving then I don't see any harm being done..

Exactly... most people don't keep new cars for more than 5 yrs (an yes it has be surveyed). Hardly worth spending unnecessary dollars etc etc for the next owner.

[Greg Roles]

It is my understanding that the needle gauge does not fluctuate off 90 in order not to distract the driver unless it is absolutely necessary to warn them about the change in temp.

That would follow with how inaccurate it is, never thought of that reasoning though, not a bad idea.

[Beaker]

Hehe so a highly strung, pushed to the limit F1 engine has what exactly in common with a Golf engine?

Actualy quite a lot, they both run dissimilar metals internaly and moving parts are kept apart by a thin layer of oil.

For example, take the big end you have a thin cup of brass/copper/aluminium alloy which expands much more and much faster then the solid crank journal it supports, as it expands the gap between them changes, in extreme cases to the point the oil can no longer maintain its film and suddenly you have metal to metal contact between two parts rotating against one another at 3000+ RPM - not so good I'd have thought!

An engine is designed to operate at a temperature, all the tollerances are set to work at that temperature - running it hard outside of those WILL damage it. Sorry thats just simple physics. In many ways modern engines are much better, and oil technology is way ahead of where it was 10 - 15 years ago, but engines these days also contain a bigger range of metals all running at tighter tollerances, so if anything they are MORE suseptable to damage running outside of optimum temperature.

You are correct that the stresses on an F1 engine are way above anything a GTI will ever see, they might be using Beryllium to cast their blocks and might be playing with Carbon Fibre pistons, but a GTI engine of today would have amazed an F1 team 30 years ago - and they warmed them up back then too.


If you spend $45K on a car, drive it how you like, but anyone who thinks it isn't damaging it to flog it cold is kidding themselves.

[Brian]

I'm struggling here guys. I've read TFM backwards, tried every combination of MFD displays, but I cannot seem to get a readout of oil temp on my MFD (118TSI). Is it not applicable to the 118 or am I missing something?
All helpful criticism will be absorbed with thanks.
Brian

[prise]

Volkswagen clearly advise against thrashing a cold engine:

On page 159 of the manual for the118TSI it says "Notice - When the engine is cold you should avoid high engine speeds, driving at full throttle and over loading the engine"
On page 240 there is a picture of the coolant temperature gauge that defines coolant temperatures below 70 deg as 'cold'
On page 19 in the description of the rev counter it says that the maximum rpm can be used "...when the engine is warm and after it has been run in properly"

This doesn't mean it has to be babied either, but there iis a big difference between brisk acceleration up to 4000 RPM and 3/4 throttle such as needed if you have to merge onto a main road vs foot to the floor and into the red-line.

[Preen59]

Oil temperature is in MFD (digital temperature), needle temperature is coolant temperature.
Just don't get to stressed up about and enjoy the car. That's to all who worry too much about touching the accelerator before oil temperature is + 80 deg.
I prefer to bring the engine to operating temperature as quickly as possible to minimize time needed to warm it up to minimize engine wear at cold.

So when you baby it for 10 min and engine is not wormed up and you already arrived to your destenation... that's definitely not good for the engine.

I give up. If you guys won't listen to an extremely knowledgable person, WITH credentials (Transporter) and are still arguing, there's no hope for you.

It's your car, so i don't really care. I doubt i'll be buying it off you second hand. The only reason most people know anything about cars is the internet, and some of them seem to think that the little they've read (and pretend to understand) makes them an expert.

Good luck to you.


Oh, and FYI, as a hole heats up, it expands, it doesn't contract. So your crank journal to big end analogy doesn't work, Beaker. If the rod gets hotter than the crank, the clearance increases, not decreases. And there are no "simple" physics in an internal combustion engine, mate. Believe me.

[Ryan_R]

What about if you stick to using the supercharger without over-revving when it's cold?

[prise]

What about if you stick to using the supercharger without over-revving when it's cold?

Read page 159 of your manual. I think the warning against using full throttle and over loading the engine covers it.

[logger]

I give up.

Just before you give up, as I am not really fussed what people do with their engines either. But I must correct something your said earlier:

...an aircraft engine, it is under full load straight away. It is also generally under more stress for a longer and more consistent length of time...

Aircraft engines are not under full load straight away? Prudent pilots warm their engines up. Apart from common sense, owing to there being more at stake, manufacturers require them to do so. I am yet to meet a pilot who starts an aircraft engine from cold and immediately subjects it to full power. It is just not the done thing.

[REXman]

Just before you give up, as I am not really fussed what people do with their engines either. But I must correct something your said earlier:
Aircraft engines are not under full load straight away? Prudent pilots warm their engines up. Apart from common sense, owing to there being more at stake, manufacturers require them to do so. I am yet to meet a pilot who starts an aircraft engine from cold and immediately subjects it to full power. It is just not the done thing.

Correct, my GF's brother is a pilot for qantas and he concurs, 'captain. Once your at altitude your cruising also.

PS warming up a car is a good thing. I have warmed up every "street" car I have had, heavily modified engines over 420HP as well as stock cars with just a TMIC, tune and TBE, pushed them hard, but all I ever did was service them well, and warm them up, and NEVER had a problem.

My girlfriend, dad and sister dont warm up there cars.. and they have 20000km, 45000km and 85000km on there cars. And in both the last cars - You can tell cause they now sound pretty of beat.

Where my old MY03 WRX I had for nearly 5.5 years - 70K clicks on it and it purred and thats a SuBie...

Pressure is good, sure, but the oils need to be warm before they operate properly and the properties are realised. And easying on a cold motor is the way.. I dont do it any other way. Some of those photos of other non related cars people put up on the net are just silly.

Where are they from? What really happened? How old are those motors? What are the real causes?

I can say one thing, It aint from warming up.

[Beaker]

I give up. If you guys won't listen to an extremely knowledgable person, WITH credentials (Transporter) and are still arguing, there's no hope for you.

It's your car, so i don't really care. I doubt i'll be buying it off you second hand. The only reason most people know anything about cars is the internet, and some of them seem to think that the little they've read (and pretend to understand) makes them an expert.

Good luck to you.


Oh, and FYI, as a hole heats up, it expands, it doesn't contract. So your crank journal to big end analogy doesn't work, Beaker. If the rod gets hotter than the crank, the clearance increases, not decreases. And there are no "simple" physics in an internal combustion engine, mate. Believe me.

Yeah I guess. 20 years building rally engines, what would I know?

Aircraft engines are always warmed up on the ground, a miss on take off can kill you, a pilot who doesn't warm engines up before take off has a death wish, in addition Aircraft engines have strict hour limits after which they MUST be stripped down and rebuilt. The piston engines used in aircraft are, as a general rule, also much less advanced then modern car engines, a mate flies a reasonably modern plane with a 4 cyl 5L pushrod/OHV Lycoming engine that makes a huge 160hp - hardly what you'd call pushing the envelope of performance. If anything aircraft engines have less in common with a Golf engine then the F1 example used earlier. The example I gave earlier with a big end is exactly the point. When you put a liquid under pressure between two surfaces close together it spreads out and holds those two surfaces apart, if you hold those surfaces a long way apart and squirt a liquid between them it simply flows out along the route of least resistance, by doing that it can't hold the surfaces apart effectivley.


That IS basic physics (surface tension of liquids + thermal expansion of metals)

I won't argue any further as everyone applies their own knowledge to any problem presented and make their own descisions on what to accept as correct, but it's always a mistake to presume the knowledge of others.

[gerhard]

I always like to have my engine nicely warmed up before caning it. I don't mean oil and water, I mean all the metals.

I've lost count of the number of cold siezes I've seen on the kart track - bozos leave the pits with a cold engine and hit anything from 10,000 to 18000rpm (depending on engine type) by the first corner. Most of these engines have 4 studs holding the head to the barrel to the crankcase, and when they seize you can see the 4 marks on the piston where uneven thermal expansion has caused friction and terminal seizure.

[HPSOV]

There is no requirement to warm up the engine on a jet aircraft because they are turbine engines. A completely different scenario to piston. On piston aircraft you MUST wait for the oil temp the get into the green band on the gauge prior to takeoff.

[pologti18t]

I always like to have my engine nicely warmed up before caning it. I don't mean oil and water, I mean all the metals.

I've lost count of the number of cold siezes I've seen on the kart track - bozos leave the pits with a cold engine and hit anything from 10,000 to 18000rpm (depending on engine type) by the first corner. Most of these engines have 4 studs holding the head to the barrel to the crankcase, and when they seize you can see the 4 marks on the piston where uneven thermal expansion has caused friction and terminal seizure.

But thats a 2 stroke engine. They can seize when they overheat as well
Not sure what the relevance is to a 4 stroke engine with a sump full of oil.