FK2 Stop/ start, should it be used?

Hi all, just a quick question regarding stop start. Whenever I'm in my car I make a habit of turning the stop start function off. For me the thought of the engine cutting out with hot oil still circulating makes me cringe.
But of course, if this was to damage the engine then why would honda put it there in the first place, am I being overly mechanically sympathetic? Are modern turbos robust and engineered well enough to cope with stop start?

RSmith1992FK2 said:

But of course, if this was to damage the engine then why would honda put it there in the first place, am I being overly mechanically sympathetic? Are modern turbos robust and engineered well enough to cope with stop start?

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Yes and yes. You've answered your own question really.

I've heard that there is a little oil pump that keeps pumping the oil when the start stop operates not sure how true this is

From what I'm told, modern turbo chargers don't need the same mechanical sympathy as say those of the 90's.

Even the boys on Mighty Car Mods say that there's no need for turbo timers and leaving engines running to 'cool down' these days. I know they don't do an exact science but they do seem to try and be as informative as they can for petrol heads.

I just can't get my head around shutting off an engine after half hour of hard driving.

Turbo timers and "cool down" hails from an age when turbos were oil-cooled, the theory being it would bake the oil if shut down when hot.

When the world switched to water cooling turbos, that problem pretty much went away.

No modern road car, turbo or not, really needs a 'cool down' period. They're designed with safety factors to cover with far, far more than you can throw at it [legally] on a public road. Something like a drift car where the air can't get over the radiator and transfer the heat out of the water is a different story.

The crux of the issue for switching a combustion engine off after hard use is heat soak, removing the assisted cooling while the temperature gradient is still on the rise, leading to uncontrolled expansion of components etc. But unless you're running the engine in a sealed test cell it's unlikely to be able to build up that much heat once it's turned off. Plus they use things like ceramic bearings (and water cooling as mentioned) for turbos to cope with temp. If Honda put start-stop on, you can be fairly sure they tested it to destruction to make sure you can't damage it going from a spirited drive to dead stop.

Also, the ECU is programmed to respond to issues like heavy load and overheating when it's in start-stop. The ECU will kick in the fan and I would assume there'll be an electric water pump to supplement it. I know my mum's Mazda still buzzes away under the bonnet even when stopped after a short drive (no turbo in that though ).

the wife cooper s as stop and start not a fan of it so switch it off

Darc174 said:

I've heard that there is a little oil pump that keeps pumping the oil when the start stop operates not sure how true this is

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Incorrect, but modern vehicles now have an auxiliary coolant pump. Or in some vehicles multiple coolant pumps to control the issue stated here

CTR_Nick said:

The crux of the issue for switching a combustion engine off after hard use is heat soak, removing the assisted cooling while the temperature gradient is still on the rise, leading to uncontrolled expansion of components etc.

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