Delayed engine shutoff WTF!!!

[Dom]

I always understood it was to let the turbo cool down for a sufficient period so as not to "cook" the oil that would be left in it once the oil pump had stopped.

[Dom]

And not saying Wikipedia is always right but it backs up everything I've been told about the matter:

From Wikipedia, the free encyclopedia
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A turbo timer is a device designed to keep an automotive engine running for a pre-specified period of time in order to automatically execute the cool-down period required to prevent premature turbo wear and failure. After a period of driving when a turbocharger has been working hard, it is important to let the engine run at idle speed for a period of time, allowing the compressor assembly to cool from the lower gas temperatures in both the exhaust and intake tracts. At the same time the lubricating oil from the engine is able to circulate properly so the turbine won't burn the lubricating oil that would otherwise be trapped within the charger with the turbine rotating at high speed. With regard to modern automotive turbochargers, the need for a turbo timer can be eliminated by simply ensuring the car does not produce any 'boost' (during driving) for several minutes prior to the ignition being shut off. Most turbo timers are based on digital electronics.

Turbo timers can usually be disabled by an external switch, this is normally done using the handbrake switch, or using an automatic one.

[wallopsri]

So many answers all saying the same.... Guess I must be off the mark....

Note to self;

1, Turbo Timers are employed to permit a turbo to cool....
2, Turbo Timers are employed to prevent oil 'coking' the insides of the turbo housing & bearings....

3, Turbo Timers are not employed to permit a fully lubricated & cooled spooling down period....
4, Turbo bearings are not affected by friction during extended unlubricated spooling down periods....
5, Turbo bearings are not affected by heat build up during uncooled & unlubricated extended spooling down periods because they don't suffer increased friction when unlubricated....
6, Technology with regards turbos, bearings & engine oil has stood still for nearly 30 years....
7, Turbine speed is always in tune to engine speed, both friction & inertia are banned from turbos....
8, Inertia plays no part in a turbines spooling down period....
9, Low inertia turbos are a myth....
10, Lighter ceramic turbine blades have no beneficial effects as inertia & friction don't exist within a turbo....
11, Turbo lag is a myth....

Nuff said... I'm totally wrong and talking out my anal orifice....

WALLY one signing off.........

[lee-170]

the saxo probly had its spare key in with it running lmao

[vantastic007]

I always like the cheap simple solution...... lmao

I am currently learning to manually wind my windows up and down smoothly so they look electric, and I turn my lights on when entering a tunnel and off again when leaving, and wipe my windows pointlessly on perfectly dry days, turn my engine off at traffic lights.... and ... and ... oh please stop me......

[Davey j]

I always understood it was to let the turbo cool down for a sufficient period so as not to "cook" the oil that would be left in it once the oil pump had stopped.

That's as I understand it too. In fact an old Toyota Avensis TD I had as a company car had a warning sticker on the sun visor saying it was equipped with a turbocharger therefore it was advised to run the car at idle for a minute after normal use to allow for adequate cooling down therefore extending bearing life.

[jordanb7426]

So many answers all saying the same.... Guess I must be off the mark....

Note to self;

1, Turbo Timers are employed to permit a turbo to cool....
2, Turbo Timers are employed to prevent oil 'coking' the insides of the turbo housing & bearings....

3, Turbo Timers are not employed to permit a fully lubricated & cooled spooling down period....
4, Turbo bearings are not affected by friction during extended unlubricated spooling down periods....
5, Turbo bearings are not affected by heat build up during uncooled & unlubricated extended spooling down periods because they don't suffer increased friction when unlubricated....
6, Technology with regards turbos, bearings & engine oil has stood still for nearly 30 years....
7, Turbine speed is always in tune to engine speed, both friction & inertia are banned from turbos....
8, Inertia plays no part in a turbines spooling down period....
9, Low inertia turbos are a myth....
10, Lighter ceramic turbine blades have no beneficial effects as inertia & friction don't exist within a turbo....
11, Turbo lag is a myth....

Nuff said... I'm totally wrong and talking out my anal orifice....

WALLY one signing off.........

where as before you just sounded like someone who has been told the wrong information at some point... now you have made yourself sound like a right idiot lmao

turbo timers are for allowing the turbo to cool down and and prevent coking and thats it, sh*t bust.

yes, if you ran the turbo up to full boost and then cut the oil supply off there would be increased wear but that is a totaly different senario.

you are trying to say that a turbo takes minutes to slow down when it quite simply doesnt! if it did rally cars would not need anti lag to keep the turbo spooled up during gear changes etc...

the reality is that it only takes a few seconds for a turbo to return to idle speed. by the time you've parked the car and got round to turning the engine off the turbo will have slowed down so no matter how long you keep the engine running the wear on shutdown will be the same

a slight exeption would be roller bearing turbos as they take longer to slow down but they still dont take long, and even if they were still spinning slightly faster than idle speed when you turned the engine off, the wear would be minimal because they have roller bearings (clues in the name ) and the residual oil in the bearings would be enough to keep them lubricated untill the turbo had stoped

also on your points 6,7,8,9+10... lighter/low inertia turbos are desighed to help spool up, nothing to do with shutting the engine off. and ironicly, due to their low inertia, would spool down faster so would be at even less risk of your so called increased wear lmao

and yes oil technology has moved on in the last 30 years. hence not that many people use turbo times these days as modern oils are more resistant to coking. people that still use them normaly just have them for piece of mind, something else to ad to the gadget list or from miss information from people like you

[Gordo]

Chill out mate.... I'm not simply regurgitating crap read off the net....

Just crap!
If you give the engine a big rev' and immediately shut it down, the turbine may run dry, but normally it's turning slowly, oil pressure doesn't drop immediately and there's a residual oil film to lubricate it.
500C will cook ANY modern oil, continuing an oil supply will make a significant reduction in the bearing temperature. As will, surprisingly, the idle temperature exhaust gases.

That said, for normal. light driving, a timer is probably not needed - it's more for when a vehicle is driven hard and then shut down with the turbo still very hot.

[Gordo]

So many answers all saying the same.... Guess I must be off the mark....

Note to self;

1, Turbo Timers are employed to permit a turbo to cool.... true
2, Turbo Timers are employed to prevent oil 'coking' the insides of the turbo housing & bearings.... true

3, Turbo Timers are not employed to permit a fully lubricated & cooled spooling down period.... don't be stupid!
4, Turbo bearings are not affected by friction during extended unlubricated spooling down periods.... of course they are - don't play dumb!
5, Turbo bearings are not affected by heat build up during uncooled & unlubricated extended spooling down periods because they don't suffer increased friction when unlubricated.... see above
6, Technology with regards turbos, bearings & engine oil has stood still for nearly 30 years.... see above
7, Turbine speed is always in tune to engine speed, both friction & inertia are banned from turbos.... false, false and false - as you know!
8, Inertia plays no part in a turbines spooling down period.... see above
9, Low inertia turbos are a myth.... see above
10, Lighter ceramic turbine blades have no beneficial effects as inertia & friction don't exist within a turbo.... see above
11, Turbo lag is a myth.... see above

Nuff said... I'm totally wrong and talking out my anal orifice....

WALLY one signing off.........

Not totally wrong - you got the first two right!

[wallopsri]

Chill out guys....

Sarcastic posts are supposed to be taken in jest.... Please accept my humble apologies if my post wasn't quite easily understood....

Be careful on those high horses lads....lmao

Wally one signing off...

[jordanb7426]

Not totally wrong - you got the first two right!

lmao

[wallopsri]

Not totally wrong - you got the first two right!

Now thats funny.... Cheers you've brightened an otherwise boring daylmao

[vxlgsi]

apologie accepted

[jordanb7426]

apologie accepted

+1

its not that we want to make you look stupid. its just like vxlgsi said before, theres a lot of myths and false info about on the net and we want to make sure people get the right information

every days a school day