How long to cool down.

[bigenginesmallcar]

Everyone always talks about waiting so many miles before booting a car engine but theoretically, how does the timing change if say you have already driven it a good 30 minutes and then 4 hours later you jump back into it.

Surely after a couple of minutes of driving itll get warm enough again to boot it a bit?

Surely you cant drive carefully for the first 5 miles on every journey even if you have used the car already and the ambient temperature is say 15 degrees or so?

I booted mine earlier after 2 minutes of pottering, it had been used on a motorway stint 4 hours prior to it and it was 15 degrees outside. (Although in my case im aware the car has some kind of blanket that keeps the engine warm for longer than a normal car - B58 Engine), but surely most engines will be fine and warm enough.

I feel like i see people booting their engines all the time and having no issues yet it seems a huge concern on online forums to wait a long time before hand. I just dont know what is right these days?

[bigenginesmallcar]

xjay1337 said:

So many factors it's impossible to tell.

You have oil temp gauge on the shadow line B58 engined cars. I would suggest checking that

Not on mine, its after 2018 i believe i dont get that luck, well i do but i have to go through menus for about 30 seconds before i get to it.

[bigenginesmallcar]

TarquinMX5 said:

hb_fash said:

I don't think it's worth worrying about.

Booting it when its less than normal operating temperature once in a while isn't going to bother any well serviced modern engine.

Old and poor quality oils are the biggest threat to modern units these days - not the occasional stab when cold. So long as you service it on time with good quality oil it will be fine.

You're obviously well-informed.

Care to share your evidence for those who don't have the benefit of your knowledge.

Well funnily enough i see tons of cars getting ragged from cold and they seem to last, also im sure if it was as bad as that the manufacture would put in some kind of thing that limits power or flash warnings or something. I do think this whole 10 mile thing before booting seems overkill.


I think i seen a chart before showing that a lot of modern oils for cars, once they reach 30 degrees or so the viscosity is barely any different to when its 100 degrees.