Correct way to warm up / cool down engine and turbos

Just wondering what the correct method is?

For warming up, is it:

(a) Until water and oil temp are in the middle, be very very gentle, do not use turbo at all. Once they have warmed up, boot as hard as you like.

(b) As above, but before "booting about as hard as you like" should you make a couple of gradual runs, say 2 or 3, before planting your foot?

© Another method - pls state

Cooling down:

10 minutes before you park up and switch engine off, drive around treating the car as if it hasn't warmed up yet and be very gentle.

Is that right? Or utter bollocks?

water temp and oil temp are 2 different things, always go with oil temp.

I might be right in saying, water might be at 80oc your oil will not.

I usually go for the last 3 miles of my journey taking it steady.

That's why I said water AND oil temp

I have noticed that whilst the water will warm up quickly, the oil take quite a bit longer.

I tend to set up my turbo timmer for all this malarky. I'll leave the car running, till its fully warmed up, oil temp at normal level.

Then when my journey has fully finished, i'll leave for at leat 5-10mins idling to cool things down,

I let mine warm up properly but i never let it tickover to cool down, i just drive the last mile or so off boost then switch it off soon as i stop.

I let mine warm up properly but i never let it tickover to cool down, i just drive the last mile or so off boost then switch it off soon as i stop.

I never leave mine switched on idling to cool it down, that's bad news.

me to, its easier and i thought better to take the last mile or so easy to cool it down while its moving than just sitting there.

I never leave mine switched on idling to cool it down, that's bad news.

Why is that?

Why is that?

Bad news for the neighbours.

Bad news for the neighbours.

Thats alright for me though, im like 6'1 and 16st of solid muscle, tend not to get hassle.

Warming up - Leaving a car on idle to warm up is proably one of the worst things you can do to an engine as it takes longer for the oil to reach temp increasing engine wear because the oil is not at its nominal temperature and cannot provide full protection.

Just drive gently until oil is at correct temperature.

Cooling down - Also drive the car gently with as little boost as possible to allow turbos to cool. Ive never needed a turbo timer and never see the need for one unless you drive the car hard all the way home.

I think the theory behind this is that when having a spirited drive alot of heat is created and if you dont allow the turbos to cool the high temps can cook the oil in the bearings of the turbos turning them into sludge and not giving enough lubrication to the bearings.

Warming up - Leaving a car on idle to warm up is proably one of the worst things you can do to an engine as it takes longer for the oil to reach temp increasing engine wear because the oil is not at its nominal temperature and cannot provide full protection.

Just drive gently until oil is at correct temperature.

 

Cooling down - Also drive the car gently with as little boost as possible to allow turbos to cool. Ive never needed a turbo timer and never see the need for one unless you drive the car hard all the way home.

I think the theory behind this is that when having a spirited drive alot of heat is created and if you dont allow the turbos to cool the high temps can cook the oil in the bearings of the turbos turning them into sludge and not giving enough lubrication to the bearings.

Thanks for that, makes perfect sense

I still find the 'not letting car idle when warming' idea a bit of a strange one.

This discussion was on pistonheads a short wile ago and there were points of view from different angles.

There is indeed the idea that the warming time period for oil at engine idle does more damage than engine oil warming period for steady driving....BUT I still think that the engine under any load when oil is cool will incur more wear and tear than when at idle.

Oil when cool still provides an amount of protection, and I think that under no engine load the oil can provide 'good enough' protection and will cause no real damage.

This view versus the idea that loading the engine on cool oil allowing it to warm up quicker seems to be more logical to me.

It is true that the warming period will be considerably less on engine load, but I still think the comparative 'damage' will be worse under the condition of engine 'load + cool oil' as opposed to 'no load + cool oil'.

A lot of car handbooks these days do state however that you should drive off as soon as you start the engine...I have a feeling that this is more to please the 'greens' rather than mechanical sympathy.

And I am still to see any time vs 'damage' graphs that shows one method being worse than the other.

I am guessing that some of the low quality oils that do not provide cool protection (ie the ones that do not have the magnetic attraction particles) may sway the argument towards driving off as soon as you start, but I am still with the other line of thinking until I see actual evidence.

Oilman may be able to give some insighted views on this.

I am new to all this really, but as far as I can see it makes a lot more sense to drive the car pretty soon after turning on, working through the gears to get the 'system flowing' rather than just letting it warm up sat somewhere. Careful driving whilst it all warms up should suffice... a bit like a parade lap

Maybe truck engine oils used to cook turbo seals back in the day but I don't see that happening with modern synthetic oils that can take much higher temps. Perhaps it's best to have an EGT gauge and turn the engine off let's say at 400C or whatever seems reasonable rather than having an expensive egg timer wired on a relay

I also don't like them as thieves could bypass the alarm system to get to the ignition (maybe?)

I still find the 'not letting car idle when warming' idea a bit of a strange one.

I always assumed it was more for the idiots out there who will leave the car on the drive for 5 mins and then get in and floor it straight away because the 'temperature guage' (water) is reading in the middle somewhere - whereas if they drive it slowly for 5 mins, then the oil will be in a much better place to protect the engine when they start flooring it.

I am guessing that some of the low quality oils that do not provide cool protection (ie the ones that do not have the magnetic attraction particles) may sway the argument towards driving off as soon as you start, but I am still with the other line of thinking until I see actual evidence.

 

 

Oilman may be able to give some insighted views on this.

I think Oilman will point you swiftly away from those magnetically charged oils!

very good thread. personally drive straight away on start up never hit boost till couple of miles.and on return last 2/3 miles of the boost and 20/30 sec at idel turn of

I drive away from cold taking it easy for the first few miles. On return I take it easy for the last couple. I use the tubo timer if I've had a particularly spirited run and end up at a pub - if so, I leave it running for a minute or so whilst I order myself a tasty bottle of kaliber.

I've had my car since 15,000 miles, and now I'm on around 94000 miles on the original turbos (j-spec) and they still push me through the air nicely.

With regards to startup I always let the engine warm up until I can see the temp gauage just going over C (cold) and then slowly start to drive away and try not to let the turbo engage for at least first 2\3 miles.

I normally do not let the car go on boost for the last couple of miles and then leave it running for 1 minute or so before I switch it off. Apprantly leaving it idle for a minute allows the oil to cool the turbo's down, which mentioned above stops problems with the turbo?

This is a very interesting thread.

Hmm Can see that most people assume that the oil is warmed up only after 2-3 miles.

It normaly takes longer than that. Want to be sure drive atleast 6-7 miles.

Me personaly always let the engine idle for 20 secs or a bit less. Then drive without boost the first 8 miles, and let it cool off when driving home the last 3-4 miles.

Turbo timer is not a good idea. You have very little oil circulation when you idle the car. And there is no fresh air brought into the system to cool it down.

Much better to let the whole engine cool down the last 3-4 miles, and then shut it off.

Hmm Can see that most people assume that the oil is warmed up only after 2-3 miles.

When I had an oil temp gauge in the car, the oil would take about 10 to 15 mins to warm up, so I am guessing about 4 to 5 miles.

well, as I'm not fully bought into the idea of driving off as soon as the engine is started, my method is that I leave it idling for about 2 minutes to get 'an amount' of heat into the engine/oil/water etc. then drive off and try to use as little boost as possible until my blitz gauge shows oil temperature above 70degrees.

70 degrees and above is considered to be in the operating temperature region for oil whereby it is giving near maximum protection. (Was told this by Tim Sugden - racing driver ---- so it must be true )

It usually takes about 5 minutes after engine start to reach 70 degrees.

And after 70 degrees I then use gradually use increasing boost until above 90degrees.

Above 90 I consider the oil at full working temp giving maximum designed protection and I boost to full as and when. (usually a further 1 - 2 minutes to get to this temp)

On cool-down I drive no-boost for the last 2 - 3 miles and when stopped I let the car idle for about 30 seconds..... I mainly do this just so that I can listen out for any unusual noises and just let everything 'settle' etc.

I think most manufacturers will have their own stated methods of driving for different engine types (petrol/diseasal/na/turbo etc), and then there will be personal tried and tested methods that will have proven to cause no ill effects. I think this is where many of the different quoted/stated methods arise form.

just wanted to add that I'm not stating the above to be the only correct way to warm up/cool down an engine (if correct at all)....this is purely my own method.

(So if your engine breaks and your turbos go flying through your bonnet followed by the bottom end falling onto the road and then the doors fall off - then its not my fault )

double post - sorry

With an oil temperature gauge in my car, it takes at least 5/6 miles of 30/40mph driving to get the oil to operating temperature at this time of year. It takes even longer in winter.

Toyota recommend warming the engine by driving, until water temperature is within normal range. Toyota will assume that driving after this point will be "normal". If you are going to use WOT it is worth waiting a few more miles before driving hard.

For cooling oil Toyota recommend idle times below

Normal city driving (30 mph) - no cooling required

50 mph driving - 20 seconds cooling

63 mph driving - 1 minute cooling

Above 63 mph, heavy driving, hill climbs etc - 2 minutes

Turbo timers are useful when stopping quickly after continued 63mph+ driving ie pulling into a motorway filling station etc.

I also wait until my oil is at 90 degrees before using significant boost.