A friend in work has told me im an idiot for starting my engine 5mins before i leave... He said it damages the engine. I would love to go back to him with some technical come backs, unless he's right?

Its a debateable subject but it has some logic...

Car left idling from cold will take longer to heat up and promote more wear. Its also feasibly not the best for rings. Best way is to steady drive, it will heat up faster.

Agree with MrDB, especially on cold mornings when the oil is like treacle - much better to get it circulating properly.

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Caldina Blog

With a turbo engine it makes more sense to ensure the oil is warm before driving with any boost. Engine wear is greatest on start up tho as you say.

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Don
GT4DC Chairman
1994 Toyota Celica GT-Four ST205WRC JDM 269bhp @ 0.9bar
1994 Toyota Celica GT-Four Special GT 590bhp @ 1.8bar
1989 Van Diemen RF88/89 Formula Ford 1600
2008 Nissan Patrol GU 3.0L ZD30DDTi 154bhp

i start mine and after 5 seconds on idle i drive off, i limit my boost for 15 minutes to not even reaching positive boost, most i hit on record in mornings before warm is -05.

and the engine and turbo is still going strong so seems a good enough way to get her warmed up

im like dale.

basically drive it like running an engine in until it gets some heat in the system.

If your doing lots of short journey's then using a thinner cold oil will be of benefit.

Hi,

you are no idiot for sure, possible just a little bit afraid, start the engine and drive the first 10km gentle do his work fine

i also wait some seconds after start up and use the time to fasten the belt and such things and then i drive

greetz

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KEEP COOL UNDER PRESSURE

street legal?.....perhaps in tschibuti

I usually warm mine up for 30 secomds or so then drive it

The exception to this is at DC meets where I usually start it when we leave the building then talk rubbish for 1/2 an hour in the freezing cold before actually driving off

So maybe i am leaving it abit long. His arguement was that its designed to run under load, any car will knacker if left idealing to long. Maybe ill agree with him on this one. But then again he is my boss, so taking 2mins to pop out and start my engine means im not working

Lol Steve I was just thinking that!

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GT4DC Events Co-ordinator
1996 ST205 UK

Tango - think it will make 2 parts of bugger all difference. The key point is not to cane the crap out of it before it's warmed through

...and then once you have caned the little blighter, let it cool down before switching off the engine

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Kris
95 ST205 - slept for 10 years, now waking up...
Avensis
http://www.gtfours.co.uk
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Turbocharging - the replacement for displacement

Letting an engine warm up slowly will do less damage then an engine not up to temperature. Don’t get confused between start up and warm up, the wear is in start up with the first few turns of the engine until the oil light goes out and the oil starts to circulate but the oil is still cold and highly viscous until warm so forcing it can also cause problems and lead to premature failures.
However manufactures take into account the way the domestic car is used and abused and build in margins for such use, even for something with a bit of performance like the GT4. It makes sense to me to let an engine stand and ideal for a minute or two before driving, even if you let it stand and ideal for 5 min it will make no difference to the longevity of the engine.
Just tell him he’s talking crap and you’re letting it warm up to reduce thermal shock, I mean when was the last time you saw a race car hit the button on the start line and take off? Dorris

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Black CS 2771

Lots of race car engines are now fitted with oil and cooling system 'T' pieces so that pre-heaters can be connected to warm up the oil and coolant before the engine is started. This substantially reduces the engine wear on initial start-up and running. You will also see some cars being run in gear while jacked up in the pits so that the transmission oil is warmed before the car takes to the track. It all helps to reduce wear.

Clearly a road car isn't fitted with such systems although on the 3S-GTE the oil/coolant 'doughnut' is designed to accelerate the heat exchanging process and speed up the engine warming process.

At the other end of the spectrum when I used to work in a big open pit gold mine in Australia the CAT773 turbo-diesel trucks were started and run for half an hour on the go line to get them warmed up before hauling the loads out of the pit.

I think there's enough evidence to say that some warming up and/or gentle running of the engine is beneficial.

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Don
GT4DC Chairman
1994 Toyota Celica GT-Four ST205WRC JDM 269bhp @ 0.9bar
1994 Toyota Celica GT-Four Special GT 590bhp @ 1.8bar
1989 Van Diemen RF88/89 Formula Ford 1600
2008 Nissan Patrol GU 3.0L ZD30DDTi 154bhp

Yes agreed! Maybe i should link this page to his facebook account?

When the engine is cold, clearances are different to when warm, also the much thicker oil will not circulate as easily. My understanding is that engine wear will be increased slightly as a result, increased much more with higher RPM where the oil just can't flow quick enough.
If you give the engine high power when cold, the pistons will warm up much quicker than the block and can cause damage due to lack of clearance. (Something we always had to take care of on the Karts - set off at full welly and sieze 100 yards later).
As Dorris says, the major wear takes place in the first couple of seconds when there is no oil pressure. After that, most opinions I've heard is that it's better to drive gently to warm the oil up quicker, although I suspect the difference is minimal.

Re. the engine being damaged by idling whether hot or cold, I can see no scenario where any components would be put under greater stress, unless he's thinking of old cars years ago with worn out oil pumps that could barely muster enough pressure to turn out the warning light at idle.

Overrun is a different matter, as the rods/pistons/rings are under quite a bit of tension to suck in air through a closed throttle, with vac. levels much higher than when idling and the forces in the opposite direction to normal. I have had a couple of engines let go on lift-off - one was big end bolt failure (over-run will put the most stress on these) and the other was a fatigued crank letting go.

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If at first you don't suck seed, try drier grain.