Warming Up the Vehicle

Derek Barnes · Senior Member

Warming Up the Vehicle

Possum3 · Guru

Allowing an engine to "warm up" lets the lubrication systems to become less sticky and will improve wear qualities of oils (more-so with Mineral oils than Synthetics) thus gaining a longer engine life due to less wear. Particularly advantageous when towing a caravan or otherwise putting a load on engine and transmissions.

outlaw40 · Guru

Little to none in australias climate unless your in the alps in the middle of winter . By the time you start up,put your seabelt on and rive moderately out of camp to the road your good to go . Same as idling down unlessyou been pulling 80 tonne up the Moombi range its not required .

Whenarewethere · Guru

Transmission needs to warm up as well. Drive gently & do not excessively rev the engine for the first km.

I have never "warmed" up an engine & they lasted over a quarter of a million km each, & still very ok.

The only time I have warmed up the engine was to get through very soft sand in the morning because there was next to no run up to it.

Derek Barnes · Senior Member

Thanks for the replies! A neighbour of ours used to start their car, have breakfast taking about half an hour, then drive away!

We have never warmed up our cars but have gotten about 500,000km and about 600,000km out of our first two cars with no engine or transmission problems. In fact the guy who bought our first car said the engine was particularly quiet.

iana · Guru

An interesting point, running the motor for prolonged periods without load, can cause glazing of the cylinder bore. I have been told that with todays close manufacturing tolerances, warming up the engine well before setting off is unnecessary. Synthetic oil viscosity is not so effected by temperature. As what Outlaw 40 says, by the time you have put on your seat belts, set the GPS, argued with the missis about where you are going, the engine will be ready to go.
Probably more important to let the engine idle for a short time to let the turbo charger spool down and cool, before turning off the motor.

oldbloke · Guru

outlaw40 wrote:
Little to none in australias climate unless your in the alps in the middle of winter . By the time you start up,put your seabelt on and rive moderately out of camp to the road your good to go . Same as idling down unlessyou been pulling 80 tonne up the Moombi range its not required .

+1

Possum3 · Guru

Derek, Perhaps some people run the motor just to use the Air-conditioner to heat or cool the car - before setting off.

bgt · Guru

We RVed in the USA for many years. Those with diesels often started them up in the morning and had breakfast before starting to pack up. It annoyed the heck out of everyone around them. Then there started to be reports of early engine failures. Long story short. Cummins found themselves in court. They had misled consumers about warm up. The court found that Cummins knew about the extra wear caused by 'morning warm ups' but still continued to 'promote' the practice. It was found that Cummins 'encouraged' it so that early wear would mean more long term sales. I forget the payout but it was more than a $1.50!

Our diesel motorhome had a block warmer. Cold weather you simply plugged the engine into the campground 120v socket. In Alaska we spoke to a mechanic who told us he spent his winters replacing diffs and universal joins. The customers would warm the engine then hurtle down the road only to find the frozen universal joins fail.

In Australia our bus conversion was a 6V92 Detriot. Idelling those would glaze the bores.

One more - We met some folks high in the Rocky mountains. Dry camping. They made a campfire each night. When the fire died down they backed their bus conversion so the engine was over the coals. Different!

No point warming up unless you warm up the entire drive train.

yobarr · Guru

iana wrote:
An interesting point, running the motor for prolonged periods without load, can cause glazing of the cylinder bore. I have been told that with todays close manufacturing tolerances, warming up the engine well before setting off is unnecessary. Synthetic oil viscosity is not so effected by temperature. As what Outlaw 40 says, by the time you have put on your seat belts, set the GPS, argued with the missis about where you are going, the engine will be ready to go.
Probably more important to let the engine idle for a short time to let the turbo charger spool down and cool, before turning off the motor.

Absolutely agree with the words above that I have highlighted,but it also is worth fitting an EGT gauge......wait until temperature drops to around 150 degrees before shutting down engine.As far as warming up,in most cases,around 30 seconds is enough,as suggested by Steve,but if air temp is lower,a minute or more may be necessary.Cheers

Whenarewethere · Guru

iana wrote:
by the time you have put on your seat belts, set the GPS, argued with the missis about where you are going, the engine will be ready to go.

Or more likely seized up!

KJB · Guru

The short , slow , easy drive out of the Park and onto the road will warm the motor plenty....ready to start some real work ..

Bobdown · Guru

Possum3 wrote:
Allowing an engine to "warm up" lets the lubrication systems to become less sticky and will improve wear qualities of oils (more-so with Mineral oils than Synthetics) thus gaining a longer engine life due to less wear. Particularly advantageous when towing a caravan or otherwise putting a load on engine and transmissions.

We always let the cars warm up a bit, usually until the Revs dies down to idle speed......30 sec or so.

Cheers Bob

outlaw40 · Guru

think about how many times you are actually PULLING full noise before you want to shut down , in most cases you have come off the power well before your ready to hit the kill switch be it a 60 kmh zone approaching the caravan park gate or even just slowing down to enter a camp ,sitting there while swmbo decides which tree to pull up under , even pulling in to fuel up the period of time it takes to pull of the road and coast up to the pump is sufficient , as soon as you saw the servo you eased of the throttle anyway so the turbo wouldnt be spooled . if your driving a b model mack maybe or maybe a 79 series ( we all no how hard you have to work them !! ) but for the modern turbo diesels idling down is not required in 99.9 % of cases .

Whenarewethere · Guru

& the tyres will get a bit warmer as well.

If you have TPMS you will be quite shocked how much pressure drops on a cold morning. So warm the tyres up as well as the rest of the car while quietly exiting the camping area & save money on fuel!

yobarr · Guru

outlaw40 wrote:
think about how many times you are actually PULLING full noise before you want to shut down , in most cases you have come off the power well before your ready to hit the kill switch be it a 60 kmh zone approaching the caravan park gate or even just slowing down to enter a camp ,sitting there while swmbo decides which tree to pull up under , even pulling in to fuel up the period of time it takes to pull of the road and coast up to the pump is sufficient , as soon as you saw the servo you eased of the throttle anyway so the turbo wouldnt be spooled . if your driving a b model mack maybe or maybe a 79 series ( we all no how hard you have to work them !! ) but for the modern turbo diesels idling down is not required in 99.9% of cases.

The fitting of an EGT will soon illustrate to you the folly of such "advice".It takes minutes for a diesel to cool to 150 degrees even when you have been running at only 250-280 degrees on the open road,let alone after a steep climb.Cheers

Mike Harding · Guru

Whilst I'm sure there is merit in the advice regarding modern engines... I still, and will always:

Run in a new engine.

Warm up a cold engine.

Allow a hot engine to cool before shutting down.

None of the above do any harm and they just may do a lot of good.

outlaw40 · Guru

We shall agree to disagree on that one yobarr ,each to his own. you do it your way and i shall do it my way ..

Whenarewethere · Guru

Leaving my garage in the morning the temperature gauge is at the same position as if it is a 47°C day, about 750 metres down the road.

Peter_n_Margaret · Guru

It takes a long time to warm up an engine at idle because very little fuel is being burnt. Driving away gently will do a better job and much faster.
Yes, a hot engine can take some minutes for the EGT to drop to 200C (which is my switch off temperature). Above that, oil trapped in the turbo can degrade, is my understanding.
The Perkins has no glow plugs and can be very difficult to start at very low temperatures (under 10C), but I can warm the whole engine using our diesel heater.
Cheers,
Peter

dogbox · Guru

Mike Harding wrote:

Whilst I'm sure there is merit in the advice regarding modern engines... I still, and will always:
Run in a new engine.
Warm up a cold engine.
Allow a hot engine to cool before shutting down.
None of the above do any harm and they just may do a lot of good.

a cold engine idling away with minimum oil pressure and possibly rich fuel mix, washing any residual lubricant from upper cylinders !!?

most of engine wear is done when starting a cold engine the quicker you get it up to operating temp the better but that is only my humble opinion i have been know to be wrong in the past

-- Edited by dogbox on Tuesday 24th of November 2020 01:57:11 PM

Mike Harding · Guru

dogbox wrote:
Mike Harding wrote:
Warm up a cold engine.
a cold engine idling away with minimum oil pressure and possibly rich fuel mix, washing any residual lubricant from upper cylinders !!?

most of engine wear is done when starting a cold engine the quicker you get it up to operating temp the better

Fair comment.

I suspect modern oils (which are amazing) have made warming-up far less important than it was; nevertheless bearing and other metal-to-metal contact areas also need to reach operating temperature in order for their clearances to be at the designed operating level.

Nowadays my practice is to allow a cold engine to idle for about 60 seconds and then drive quite gently for the first two minutes and just gently for the next two - this is not an exact science :)

What I *do not* do is hang 3T of caravan off the back and expect a cold engine to pull it up a hill within two minutes of starting.

I take your point on the excess fuel (do diesels do that?) but at idle the engine is hardly doing anything power wise so probably doesn't need much lubrication - how two-strokes work with their miniscule lubrication is still beyond me! :)

yobarr · Guru

Whenarewethere wrote:
Leaving my garage in the morning the temperature gauge is at the same position as if it is a 47°C day, about 750 metres down the road.

Hi Jonathan.....I'm not much chop on identifying smaller cars,but is your car a petrol model? Cheers

Whenarewethere · Guru

yobarr wrote:
Whenarewethere wrote:
Leaving my garage in the morning the temperature gauge is at the same position as if it is a 47°C day, about 750 metres down the road.
Hi Jonathan.....I'm not much chop on identifying smaller cars,but is your car a petrol model? Cheers

9 out of 10 Freelanders & Evoques have a 2.2L diesel engine, my sister has an Evoque with the oil burner. Mine has a Ford Ecoboost 2.0L petrol engine.

We had a yacht with a diesel engine & never bothered to warm it up.

Nevd · Senior Member

My trusted diesel mechanic has told me not to warm up a diesel because of the potential glazing of the bores. He's worked on diesel engines for years, so should know. This has been backed up by several industry articles I have read over the years.

Here's just a couple -

https://www.whichcar.com.au/car-advice/winters-coming-how-should-i-warm-up-my-car

https://www.berrimadiesel.com/diesel-archives/warm-up-a-diesel

So by the time you start up, hitch up and connect the cables, you're good to go (gently though).

yobarr · Guru

Whenarewethere wrote:
yobarr wrote:
Whenarewethere wrote:
Leaving my garage in the morning the temperature gauge is at the same position as if it is a 47°C day, about 750 metres down the road.
Hi Jonathan.....I'm not much chop on identifying smaller cars,but is your car a petrol model? Cheers
9 out of 10 Freelanders & Evoques have a 2.2L diesel engine, my sister has an Evoque with the oil burner. Mine has a Ford Ecoboost 2.0L petrol engine.
We had a yacht with a diesel engine & never bothered to warm it up.

Thanks Jonathan.....found this on Dr Google,and thought it may interest others? Cheers

Bobdown · Guru

No one leaves their car warming up for 5 - 10 minutes, that's ridiculous.
Both our Toyotas rev up to 2500 -3000 rpm when you start them, 15 - 20 seconds later they drop down to approx 600 rpm.
It has not 'warmed up' fully but enough to drive off safely.

Cheers Bob

Tony LEE · Guru

"No one leaves their car warming up for 5 - 10 minutes, that's ridiculous."......... Quite so. Even the Americans don't leave their vehicles idling for that short a time. Try 30 minutes. At start up and shut down....or the whole time they are in Walmarts A few states have no-idle laws but I doubt whether too many take notice.

Whenarewethere · Guru

My car is off the dial when it starts & when it is 1°C!

Izabarack · Guru

Peter_n_Margaret wrote:
It takes a long time to warm up an engine at idle because very little fuel is being burnt.

Totally agree. My DMax started cold and left idle will not move the temp gauge off the stops in 5 minutes. The contrast is that a gentle acceleration moving off and the temp gauge indicates operating temp inside a Kilometre or so.

I also use 5W40 semi synthetic oil. No need to warm the oil as full oil pressure takes seconds to achieve.

Iza