How long before engine oil is fully warm (petrol & diesel)?

[VeeFource]

Petrolsmasher said:

But there isent much difference in oil viscosity between 30 and 90 degrees in a modern oil like 5w30 so does it matter much really?

A quick bit of googling shows the kinematic viscosity of 0W30 is about 4-5 times higher at 30°C vs 80°C.

Spare tyre said:

Of course the time of year and how long the car is parked makes a big difference

My oil temp gauge is located in my oil sump plug and amazingly it only takes 5 mins for the oil to cool from 80+°C to ~65°C. It's not like it shoots back up again when continuing to drive either, though it is a bit quicker than warming up from stone cold.

[budgie smuggler]

Petrolsmasher said:

wow after reading this thread about how long people wait til opening up the taps i feel like i abuse my car.

In summer when its warm ill wait til 5 mins of driving as past then start to work it.

In winter usually more like 10 to 15 mins, but i never wait til ive driven 10 miles, jesus i would never have any fun if i did that!!

I don't have a choice, after getting out of my driveway I've got 30 seconds on the flat, then up a steep hill and join a fast moving road on a steeper hill which quite often requires full berries to match the traffic speed.

[SidewaysSi]

Depends on which car I am in but something like the Seven I wait around 20 mind with a max of 3k revs or so.

[Exige77]

Petrolsmasher said:

Exige77 said:

The only way to really know is by having an oil temp gauge.

It does take a lot longer than people think to get oil temps up.

But there isent much difference in oil viscosity between 30 and 90 degrees in a modern oil like 5w30 so does it matter much really?

You need to get all your metal parts up to temp and fully expanded. It’s not just getting oil up to temps. The oil being hot is indication all the metal is hot.

[Condi]

Just drive it like its supposed to be driven... In the UK with a modern engine there is no need to baby it, as long as you allow the oil to get up to pressure before revving it hard you wont do any damage.

[jimPH]

My GTR which seems to measure everything shows engine oil lagging behind coolant. But even further than that is gearbox oil temperature.

I wait for all three to get up to temperature before putting my foot in.

I've recently fitted a new gearbox to my 996, which has a pressurised oil supply, so I've asked for the temperature gauge to be hooked up on that too.

[Exige77]

Condi said:

Just drive it like its supposed to be driven... In the UK with a modern engine there is no need to baby it, as long as you allow the oil to get up to pressure before revving it hard you wont do any damage.

It takes seconds for the oil to be “up to pressure”.

That’s not very good advice.

[Mike335i]

Exige77 said:

It takes seconds for the oil to be “up to pressure”.

That’s not very good advice.

Agreed, some care and mechanical sympathy will pay dividends if you are keeping the car for any length of time.

I keep things gentle until the oil guage move off the 70 degree C stop. It then quickly rises to its running temp of about 100 degrees.

[Condi]

Exige77 said:

It takes seconds for the oil to be “up to pressure”.

That’s not very good advice.

It is good advice for 99% of cars and 99% of motorists.

Millions of cars are driven every day with no care at all for warming up oil, and the same engines will often do big miles before something else on the car fails and it is scrapped. How often do you hear of an engine failing these days? Its very rare, even the cheapest mass produced engines will do 200k or more with no care other than standard servicing. We live in one of the most temperate climates in the world, with top grade oil in almost all vehicles. It really isnt an isssue, and hasn't been since the 1950s!

Allowing the car to idle for a bit before shutting down is far more important than it warming up, at least for engines with a turbo. The worst thing you can do is starve a hard working turbo of oil while it is still incredibly hot.

[Exige77]

Condi said:

Exige77 said:

It takes seconds for the oil to be “up to pressure”.

That’s not very good advice.

It is good advice for 99% of cars and 99% of motorists.

Millions of cars are driven every day with no care at all for warming up oil, and the same engines will often do big miles before something else on the car fails and it is scrapped. How often do you hear of an engine failing these days? Its very rare, even the cheapest mass produced engines will do 200k or more with no care other than standard servicing. We live in one of the most temperate climates in the world, with top grade oil in almost all vehicles. It really isnt an isssue, and hasn't been since the 1950s!

Allowing the car to idle for a bit before shutting down is far more important than it warming up, at least for engines with a turbo. The worst thing you can do is starve a hard working turbo of oil while it is still incredibly hot.

You did say it was OK to “rev it hard” after oil up to pressure (few secs).

Are you still saying that’s good advice ?

If you’re going to drive it carefully (99% of people) then there’s no need to warn everything up.

This thread is about how long it takes to get oil up to temp I believe ?

[Wooda80]

A tale of 2 PHers this morning

One is a club racer sat in the paddock at Donington or Castle Combe. His car has been run down to scrutineering this morning and the engine is running while he's sat in the collecting area waiting for practice / quali. After 3 laps just to remind himself which way the road goes he goes for it and after 15 minutes he's back in the paddock having set a time.

The other is setting off in his delicate flower of a car, carefully driving around his suburb in circles to get some heat in the car and you mustn't let it idle. After 20 minutes he's ready to set off "on a blast" behind Doris on her way to Sainsburys in her Jazz and Jason on his way back from the gym in his 320d

[Mike335i]

Wooda80 said:

A tale of 2 PHers this morning

One is a club racer sat in the paddock at Donington or Castle Combe. His car has been run down to scrutineering this morning and the engine is running while he's sat in the collecting area waiting for practice / quali. After 3 laps just to remind himself which way the road goes he goes for it and after 15 minutes he's back in the paddock having set a time.

The other is setting off in his delicate flower of a car, carefully driving around his suburb in circles to get some heat in the car and you mustn't let it idle. After 20 minutes he's ready to set off "on a blast" behind Doris on her way to Sainsburys in her Jazz and Jason on his way back from the gym in his 320d

Haha, ok take your point, but the 320d needs to last 150k+ miles and we are talking about not thrashing a car, just driving it normally until it is warm.

Besides, no one wants an idling diesel, smelly noisy things haha

[A900ss]

Wooda80 said:

A tale of 2 PHers this morning

One is a club racer sat in the paddock at Donington or Castle Combe. His car has been run down to scrutineering this morning and the engine is running while he's sat in the collecting area waiting for practice / quali. After 3 laps just to remind himself which way the road goes he goes for it and after 15 minutes he's back in the paddock having set a time.

The other is setting off in his delicate flower of a car, carefully driving around his suburb in circles to get some heat in the car and you mustn't let it idle. After 20 minutes he's ready to set off "on a blast" behind Doris on her way to Sainsburys in her Jazz and Jason on his way back from the gym in his 320d

And your point is...

The first will require MUCH more maintenance/engine rebuilds than the second.

[l354uge]

Condi said:

Exige77 said:

It takes seconds for the oil to be “up to pressure”.

That’s not very good advice.

It is good advice for 99% of cars and 99% of motorists.

Millions of cars are driven every day with no care at all for warming up oil, and the same engines will often do big miles before something else on the car fails and it is scrapped. How often do you hear of an engine failing these days? Its very rare, even the cheapest mass produced engines will do 200k or more with no care other than standard servicing. We live in one of the most temperate climates in the world, with top grade oil in almost all vehicles. It really isnt an isssue, and hasn't been since the 1950s!

Allowing the car to idle for a bit before shutting down is far more important than it warming up, at least for engines with a turbo. The worst thing you can do is starve a hard working turbo of oil while it is still incredibly hot.

Nearly all these modern engines you talk of have an auxiliary coolant pump for the turbo that runs after key off.

[Pan Pan Pan]

Petrol engines seem to warm up much quicker than diesels, Probably because diesels rev at around half the speed of an equivalent petrol unit.
At 70 mph my diesel is barely doing 2000 rpm, it therefore takes about twice as long to reach full operating temp, compared to my petrol car. The water temp however in both cars seems to come up much quicker than the oil temp.

[anonymous-user]

Babying a car from cold start is counter-productive because it makes warm-up even slower.

Best to get a bit of warmth before using all the revs but what damages an engine isn't revs from cold, it's torque from cold. So better to use a few extra revs than to labour the engine in low gear.

If you want to look after your engine, drive normally and treat your engine the same way an automatic transmission would treat it (without kickdown).

And start driving as soon as oil pressure is up.

[anonymous-user]

Pan Pan Pan said:

Petrol engines seem to warm up much quicker than diesels, Probably because diesels rev at around half the speed of an equivalent petrol unit.
At 70 mph my diesel is barely doing 2000 rpm, it therefore takes about twice as long to reach full operating temp, compared to my petrol car. The water temp however in both cars seems to come up much quicker than the oil temp.

Diesels are much more thermally efficient than petrols, i.e. they don’t produce as much waste heat, which is why they take longer to warm up.

[l354uge]

rockin said:

Babying a car from cold start is counter-productive because it makes warm-up even slower.

Best to get a bit of warmth before using all the revs but what damages an engine isn't revs from cold, it's torque from cold. So better to use a few extra revs than to labour the engine in low gear.

If you want to look after your engine, drive normally and treat your engine the same way an automatic transmission would treat it (without kickdown).

And start driving as soon as oil pressure is up.

This. When I worked in engine testing the warm up procedure was 10 seconds idle, 3 minutes at 3000rpm (petrol) low load. That was for dev engines we wanted to keep alive long as possible.
Some durability ones ramped from a 1 minute idle to 3000rpm WOT..

[Condi]

l354uge said:

rockin said:

Babying a car from cold start is counter-productive because it makes warm-up even slower.

Best to get a bit of warmth before using all the revs but what damages an engine isn't revs from cold, it's torque from cold. So better to use a few extra revs than to labour the engine in low gear.

If you want to look after your engine, drive normally and treat your engine the same way an automatic transmission would treat it (without kickdown).

And start driving as soon as oil pressure is up.

This. When I worked in engine testing the warm up procedure was 10 seconds idle, 3 minutes at 3000rpm (petrol) low load. That was for dev engines we wanted to keep alive long as possible.
Some durability ones ramped from a 1 minute idle to 3000rpm WOT..

You cant come here with that common sense....

Engines have to be treated like they're made of cheese until everything right down the rear diff oil is totally up to temperature, only then can they be used properly!

[Petrolsmasher]

fk me how delicate do loads of you treat your cars, engines arent that fragile for crying out loud, i know people (not me) who thrash theres from cold all the time and they still have the same engine.

Youd think you lot were trying to prevent global warming or something, 20 minutes of driving first pahahahahaha.