How to properly drive q50 ?
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Just drive easy the last couple of minutes. My driveway is a tad over 600' long so I just go 10 MPH. If I spanked it on the road before my driveway I don't shut it off as soon as I put it in park. I unbuckle my seat belt and gather my things then shut it off. That's an additional 30 or so seconds.
if the fans are on, I let it run. if oil 180 or less, I shut it off as it does no good. even with a box fan pointed at the oil cooler
I once had a Porsche 944 turbo that was engineered correctly (except timing belt). It had a secondary electric water pump just for the turbo to cool it down after the engine shut off. It also had a 'oil catcher' built into the oil filler neck.
The point of allowing the turbos to cool is so the oil doesn't cook up around the bearings due to high temps. Conventional oils will turn to sludge and block oil flow if that happens.
The point of allowing the turbos to cool is so the oil doesn't cook up around the bearings due to high temps. Conventional oils will turn to sludge and block oil flow if that happens.
I used to have a Greddy turbo timer on a previous car. It would stay on for about 30 seconds or so after I turned the car off and got out. It always cracked me up when I'd be walking away-keys in hand-and someone would say "your car is still running". 😆
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A good question given the history of turbos, the oil pump stays on for a few minutes even after you turn off the car to allow oil to circulate and carry heat away
from the turbos to avoid this specific issue.
As others have said you only really need to let her cool-down if you had been pushing her hard just before parking, at that point
you want to give it a few minutes or if on a track take the time for a cooldown lap or two before turning in.
How would the oil pump run with the engine off considering it is rotated by the crank?
It doesn't. I'm not sure what BHC is talking about. The oil pump will not run after the engine is shut off.
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I agree that the oil is not circulating after the engine shuts off. It would be a nice feature though, if they did.
As far as letting it cool down, I always let it idle for a bit (nothing excessive). More importantly, it's better to drive slow and gently first versus just idling, for better circulation and oil pressure than it just 'sitting' with engine at idle speed.
The center section and its bearings get quite hot and simply shutting it off * can * lead to oil coking. If you've ever seen how small the passages are, it would make sense to make every effort to keep them from getting any smaller and/or having a 'crusty' coating.
As far as letting it cool down, I always let it idle for a bit (nothing excessive). More importantly, it's better to drive slow and gently first versus just idling, for better circulation and oil pressure than it just 'sitting' with engine at idle speed.
The center section and its bearings get quite hot and simply shutting it off * can * lead to oil coking. If you've ever seen how small the passages are, it would make sense to make every effort to keep them from getting any smaller and/or having a 'crusty' coating.
Then open the hood and...
The turbos are both oil and water cooled. You do not want to turn your engine off when the turbines are still spinning quickly after a pull, it shouldn't take more than a minute after a decent WOT pull for the turbines to fully slow down though. You don't want to do a massive pull, and immediately turn off into a parking lot and shut off within 10 seconds. However the time it take to slowly drive up your neighborhood road, into drive way, into garage etc... Should be plenty of time for the turbines to slow down and everything to cool down to a reasonable temp. Idling beyond that wont really do much. Mainly you just don't want to stop oil circulation while the turbines are still spinning in excess.
In non water cooled turbos a turbo timer is used to keep circulation going for about 30second after engine shut off. This isn't needed in water cooled applications as it doesn't get as hot and cools down quicker off boost.
Really it comes down to conditions leading up to shutting down, if you just beat on her for 30mins on a track that's a different story than a 20min commute home where you had a little fun on the way. the former could use some good cooldown laps, the later the roads leading to your house should be plenty of time.
In non water cooled turbos a turbo timer is used to keep circulation going for about 30second after engine shut off. This isn't needed in water cooled applications as it doesn't get as hot and cools down quicker off boost.
Really it comes down to conditions leading up to shutting down, if you just beat on her for 30mins on a track that's a different story than a 20min commute home where you had a little fun on the way. the former could use some good cooldown laps, the later the roads leading to your house should be plenty of time.
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Leeet me double check on that, wonder if I was looking at the 2.0T engine from Mercedes by mistake....
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Okay not totally crazy, its a dedicated cooling pump not an oil pump.
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Even without knowing this I wasn’t concerned. Now doubly so. Good info.
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Did they ever really stop?
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