Turbo/supercharger warm up/cool down

Ricochet J

Ricochet J

Ricochet J

Soldato
Joined
29 Jun 2004
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Do you warm up your turbo/supercharger before you set off? More importantly do you let it cool down after a journey?


Reason I'm asking is I'm going to be looking for a non shagged MK3 TDCI Mondeo Ghia X, and most probably the driver wouldn't have looked aftered the turbo since these are more or less rep cars.
 
Well I personally keep off boost for a good 20 mins on a cold start and before I’m on the way home do the same, now I don’t do this all the time but it’s a rule I try to stay to. How much it has an effect on the Turbos life who knows? :)
 
I always warm the engine up before giving it a thrash, which intern will have the oil warm enough to protect the hair dryer attached to my diseasal engine ;)

I always give it a good amount of time before turning the engine up when I arrive at my destination, although I prefer to 'drive like a grandad' when I'm near my destination so the turbo isn't uber hot.
 
I do on my car but then its a turbo petrol car. I just dont use any boost until the oil is up to temperature and then I drive the last couple of miles off the dual carriage way home sedately to let it cool down a bit. I couldnt tell you conclusively that it prolongs the life of the turbo but then it cant do any harm.

The problem with turbo diesels, is that you cant really warm the oil up before the turbo is virtually spinning up at full speed as they kick in at such low rpms and if you do, you must be driving around about the speed of a slug. I suspect most owners of turbo diesels dont even think about letting them cool down.
 
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Mind you I imagine most people in TD's probably don't nail it around and are even less likley to around residential roads. Also most TD's are so under-tuned the turbos are often running at a fraction of what they are capable of doing.
 
It's pretty difficult to drive a turbo diesel off boost. I also read somewhere that giving the turbo time to cool down on a diesel isn't so much of an issue due to lower engine speeds.

Taking it easy for the first 10-15 minutes certainly won't it any harm, but as Bear said, I doubt many diesel owners even think about giving the turbo time to warm up/cool down.
 
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I doubt any diesel turbo owners do anything like you have suggested. I'm also pretty sure it wont matter 1 bit. All the turbo diesel vans out there will be ragged from cold and they arn't known for needing replacement turbos even with milages over 150K.
 
My work van, get in, let it idle for 10 seconds while i put all my stuff away (ipod, tomtom etc), then accelerate up the road normally (white van man welded foot ;) )

Come to stop, just turn it off.

Aint blown the turbo yet on 124k, but it is a eeeny meeeny teeeeny turbo and cant be very stressed.
 
I'd say a turbo car needs the same treatment as a n/a car when warming up. I keep below 3500 RPM for 10 minutes, it's quite drivable like this and stays off the power cam.

Cooling down is where it differs, usually just a case of not thrashing the turbo and then turning the engine (and oil supply) off.
 
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i alway let the engine get up to operating temps before nailing it anywhere, and do my best to drive like a granny when close to my desination and idle the car for around 20 secs before switching off.
 
I've always understood it to be oil temperature that's the important factor, not the temp of the components themselves. Turbos will heat up and cool down a gazillion times, it's when you don't allow the oil to cool down (or heat up for that matter) that the problems can start.
 
The_Dark_Side said:
I've always understood it to be oil temperature that's the important factor, not the temp of the components themselves. Turbos will heat up and cool down a gazillion times, it's when you don't allow the oil to cool down (or heat up for that matter) that the problems can start.
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Well in this case it is the temp of the turbo that is the issue. Turbo is really hot when you've been getting on it due to the high EGT. Shut off the engine while the turbo is red hot and the oil in the turbo at that moment will get cooked to hell. The idea is to go easy so the turbo cools down and the oil doesn't get baked so much when the flow stops.
 
the warming up from cold and cooling from (HOT) are both equally important

but if youve just dawdled home doing 100% normal driving then you wont have to sit there for 60 seconds on the driveway, if anything that will probably make the turbo/oil hotter

if youve just been giving your car pure death (ie manifold glowing type stuff) then yeah, definately let this thing cool. when the oil circulation stops inside a red hot turbo, it will bake onto the bearings etc slowly leading to its death
 
I try to do as much of my cooling down as I can while on the move. Oil pressures are higher and the oil is flowing quicker while moving meaning more heat is removed from the turbo.

As you just pointed out Matt, heat soak will kick in if it's just sat there idling.
 
Clarkey said:
sorry but you are wrong, modern TD's often run with huge boost pressure.
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Yeup even the rubbish 105bhp 1.9 TDI Vag unit runs 1bar of boost, the 150bhp version runs a snip under 1.5 bar. In comparison the 180 bhp 1.8T petrol ran just over 0.5bar standard. What goes in a diesels favour is the exhaust gas temps they are around 300c lower than a petrol helping keep the turbo cooler.
 
Clarkey said:
sorry but you are wrong, modern TD's often run with huge boost pressure.
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But diesels have lower EGTs than petrol engines, so the turbo's don't get as hot. Looking at the sheer number of TD's have have done big mileages on the original turbo I don't think it's anything like the problem it is (or is perceived to be) with turbocharged petrol engines, and even then the issues were far more prevalent with early non-watercooled turbos using mineral oils.
 
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