Do you do a warm up & warm down of your moho engine ?

Whose recieved wisdom ? Where’s the evidence based research ?
This so far is purely anecdotal.
I’m open to facts ,
Interesting discussion tho 💡👍
If your on track generally the first lap is a warm up for both car and driver, then go for a hot laps then on the final lap it’s a slower lap that helps cool things down a little ( the car is still hot but won’t be as hot as at the end of a hot lap if that makes sense)
 
My 300bhp VX220 got too hot being thrashed around a track in the south of France at the height of the summer. No malfunction just extreme use.
Hope you did a ‘cool down’ lap at the end. 😉
 
I owned a 2012 6.5L Powerstroke Diesel based American motorhome The handbook advised that if the engine had been working hard a 10 minute warm down on tickover was required to protect the turbo. Problem was I’ve never heard a noisier vehicle on tickover, it was crazy/annoyingly loud. Only ever got to about 5 minutes before turning it off.
 
Stop start is so manufacturers meet green targets…they do not concern themselves as to how good it is ( or not) for the life of the engine.
I always switch off stop/start function in my Moho and in my cars.
It’s just a repeated mechanical activity that is simply not required.
When stationed in Germany for 20 years of my service life, I remember arriving and out for the first time in town in the car. Stopped at some traffic lights and promptly received a knock on my window by a passing German lady, who told me rather sternly to switch off the engine. When I did I realised that my old Vauxhall was the only car that was in the queue running. This was way before start stop technology was even built into our cars. From that day on, I always switched off at traffic lights and railway barriers etc.

It’s certainly not to meet green targets, but if we all followed the German example, then the air quality would be so much better for everyone. With the Germans, they’re taught this, along with first aid training, motorway driving and basic car maintenance, as part of their test. Makes us look pretty silly with the basic driving test we have. If we taught the rule of switching off when able, plus motorway driving, then it could only be a good thing 👍🏻

Here’s the sign that’s on so many traffic lights and crossings 👍🏻
IMG_3863.jpeg

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I owned a 2012 6.5L Powerstroke Diesel based American motorhome The handbook advised that if the engine had been working hard a 10 minute warm down on tickover was required to protect the turbo. Problem was I’ve never heard a noisier vehicle on tickover, it was crazy/annoyingly loud. Only ever got to about 5 minutes before turning it off.
How do you manage at a filling station with these sort of trucks, do you just have to sit there and let others queue behind?
 
I owned a 2012 6.5L Powerstroke Diesel based American motorhome The handbook advised that if the engine had been working hard a 10 minute warm down on tickover was required to protect the turbo. Problem was I’ve never heard a noisier vehicle on tickover, it was crazy/annoyingly loud. Only ever got to about 5 minutes before turning it off.
I think the key is to not work it hard just before you are due to stop. If I have been for a spirited run in either of my cars I will drive them gently for the last mile or so. Better than idling at a stand still as air is still flowing.

With the motorhome - well it rarely has a spirited drive.
 
I think the key is to not work it hard just before you are due to stop. If I have been for a spirited run in either of my cars I will drive them gently for the last mile or so. Better than idling at a stand still as air is still flowing.

With the motorhome - well it rarely has a spirited drive.
I think the only time a motorhome engine would be working hard enough for it to be a real concern would be at the top of a mountain pass stopping at a viewpoint
 
Fun fact. My performance car actually has an oil warmer. Coolant water has a heat exchanger with the oil. Water is pretty much always hotter than the oil...

Oil coolers (air/oil) exist of course but not on any normal production engine AFAIK.

There is an oil warmer/ heat exchanger on my original LHD 1989 T25TD VW Westfalia California.
It is based on the Caravelle model before converting.

This model was designed to comply with German Army specifications and also has a fuel warming diesel fuel filter+ an extra independent water pump which is designed to stop it overheating in desert conditions and to keep the turbo cool when ignition is switched off.
All is original and not added! 😄
 
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I wonder why we worry when most american trucks without APC's still idle overnight . Even the new ones with common rail & emissions tat.
How do you manage at a filling station with these sort of trucks, do you just have to sit there and let others queue behind?
Most trucks in the U.S. fill from both sides at once & stay on the fuel island for ages .30minutes isn't unusual on some of the programmes I regularly watch.: Often they have to wait in queues.
In the Uk I usually queue to get on a pump so it has idled & cooled whilst I wait.

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I owned a 2012 6.5L Powerstroke Diesel based American motorhome The handbook advised that if the engine had been working hard a 10 minute warm down on tickover was required to protect the turbo. Problem was I’ve never heard a noisier vehicle on tickover, it was crazy/annoyingly loud. Only ever got to about 5 minutes before turning it off.
I suspect you mostly did at least five minutes of not-hard driving before you came to a stop. Unless you were racing up Pike's Peak..?
 
Is that true or a myth with diesels? With petrol I can see a small amount of unburnt fuel escaping eveytime you start but not with diesel also if you start the engine yourself a lot tend to rev it but it doesn't do that on stop start. Those things together with the fact that stop start reduces fuel consumption and is needed to meet emissions targets suggests to me that thinking there's more pollution using stop start is an urban myth
Yes complete myth, burning fuel is the sole cause of pollutants with ICE engines, and any measure to reduce fuel burning will reduce the pollutants. Stop /start Euro6 + engines will demand a little extra alternator input, but manufacturers have this covered with efficient battery management systems controlling the charge rate.
 
I wonder why we worry when most american trucks without APC's still idle overnight . Even the new ones with common rail & emissions tat.

Most trucks in the U.S. fill from both sides at once & stay on the fuel island for ages .30minutes isn't unusual on some of the programmes I regularly watch.: Often they have to wait in queues.
In the Uk I usually queue to get on a pump so it has idled & cooled whilst I wait.
On the continent and in the UK, there are reserve fuel fill up lanes for HGV's, I wouldn't recommend using these on sub 3.5 ton vehicles unless you're very careful! 😱
 
My 300bhp VX220 got too hot being thrashed around a track in the south of France at the height of the summer. No malfunction just extreme use.
Just given me a great idea. Think a VX220 would be excellent for a toad...
 
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When stationed in Germany for 20 years of my service life, I remember arriving and out for the first time in town in the car. Stopped at some traffic lights and promptly received a knock on my window by a passing German lady, who told me rather sternly to switch off the engine. When I did I realised that my old Vauxhall was the only car that was in the queue running. This was way before start stop technology was even built into our cars. From that day on, I always switched off at traffic lights and railway barriers etc.

It’s certainly not to meet green targets, but if we all followed the German example, then the air quality would be so much better for everyone. With the Germans, they’re taught this, along with first aid training, motorway driving and basic car maintenance, as part of their test. Makes us look pretty silly with the basic driving test we have. If we taught the rule of switching off when able, plus motorway driving, then it could only be a good thing 👍🏻

Here’s the sign that’s on so many traffic lights and crossings 👍🏻
View attachment 953472

I can understand turning off ones engine if your going to be stopped for a number of minutes but, in the past, we were always told that an engine burns more fuel on startup, especially when cold.

If, in Germany, you live in town and a minute after leaving home you hit your first traffic light, followed closely by others when your engine is still cold especially in North Germany.
How does what you describe help emissions? 🤔

This doesn't include stop start hybrid vehicle of course.

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Does my nut in if you're parked next to an "idler" on an Aire or parking spot. 😁 These are commercial engines thrashed for millions of miles by white van man. Just turn the key, drive away / park up turn it off, open beer!

White Van Man probably doesn't own the vehicle, what does he care if it lasts? 🤔
 
I can understand turning off ones engine if your going to be stopped for a number of minutes but, in the past, we were always told that an engine burns more fuel on startup, especially when cold.

If, in Germany, you live in town and a minute after leaving home you hit your first traffic light, followed closely by others when your engine is still cold especially in North Germany.
How does what you describe help emissions? 🤔
In the old days of petrol carburettors perhaps there was some truth in cold startup burning more fuel.
 
Yes complete myth, burning fuel is the sole cause of pollutants with ICE engines, and any measure to reduce fuel burning will reduce the pollutants. Stop /start Euro6 + engines will demand a little extra alternator input, but manufacturers have this covered with efficient battery management systems controlling the charge rate.
Normally exhaust system condensation rather than unburnt fuel.
 
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and you think this no longer applies even at a lesser degree? 🤔
Cold startup uses more fuel - both carb and injection employ cold start enrichment with injection being somewhat more precise.

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I think the key is to not work it hard just before you are due to stop. If I have been for a spirited run in either of my cars I will drive them gently for the last mile or so. Better than idling at a stand still as air is still flowing.

With the motorhome - well it rarely has a spirited drive.
if I did a spirited drive in the MoHo it would not be staying in the black stuff and definitely in the kitty litter🤣
 
When stationed in Germany for 20 years of my service life, I remember arriving and out for the first time in town in the car. Stopped at some traffic lights and promptly received a knock on my window by a passing German lady, who told me rather sternly to switch off the engine. When I did I realised that my old Vauxhall was the only car that was in the queue running. This was way before start stop technology was even built into our cars. From that day on, I always switched off at traffic lights and railway barriers etc.

It’s certainly not to meet green targets, but if we all followed the German example, then the air quality would be so much better for everyone. With the Germans, they’re taught this, along with first aid training, motorway driving and basic car maintenance, as part of their test. Makes us look pretty silly with the basic driving test we have. If we taught the rule of switching off when able, plus motorway driving, then it could only be a good thing 👍🏻

Here’s the sign that’s on so many traffic lights and crossings 👍🏻
View attachment 953472
If many Germans just slowed down a bit & did not hare up to every junction only to rapildly apply the brakes, reduced autobahn speeds to fuel efficient levels, that would save a lot of fuel & pollution, including brake dust etc, IMHO. piously switching the engine off at a stop is probably minimaly contributing compared to those other factors!
 
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All turbos require a supply of fresh oil to bathe in and letting them idle on startup will allow fresh oil to circulate around the turbos bearings, before we put it under load. A diesel engine may well be cruising at 2-3000 rpm (as an example) while the turbo may well be doing 200,000rpm. It needs lots of oil.

Therefore running it down is essential, so that when the engine stops and the red hot turbo isn’t spinning in a pool of oil that’s also red hot, at this amazing rpm, but not getting the fresh oil around it. This way the oil can quickly fail at the very place that you need it to work. Allowing the engine to idle, will allow the turbo to slow down, spinning in a continuous supply of oil, that’s helping to cool and lubricate it.

Some manufacturers have a hydraulic spring plunger system fitted, that compresses under normal oil pressure and then when Joe Public flys down the motorway, pulls up in the service station or home and immediately switches off the engine, the spring will slowly reassure itself and deliver a supply of oil to the turbo bearing to assist in getting it cool and lubricated. Probably stop start systems springs to mind.

Laugh or disbelieve, it’s your turbo so to speak and the theory of not letting diesel engines idle certainly doesn’t stand up in my training circles. I let mine idle endlessly if needs be, always have 👍🏻

Modern turbos are an engineering marvel these days, especially when fitted with a variable vein system.

Variable vein In operation.
View attachment 953273

Coked up and failed for whatever reason.

View attachment 953275
Thanks for that info :)
 
When I was taught to drive, it was all about minimising wear & tear on the vehicle, ie drive smoothly, stop smoothly, anticipate & reduce/increase speed & thus wear & tear on many parts of the vehicle, by acting in a mechanically sensitive manner :Eeek:
My self employed driving instructor was a bit of a stickler 🤯 for not in any way causing excessive running wear on his vehicle, let alone damage!! So that is why I drive like that 🐱
 
If many Germans just slowed down a bit & did not hare up to every junction only to rapildly apply the brakes, reduced autobahn speeds to fuel efficient levels, that would save a lot of fuel & pollution, including brake dust etc, IMHO. piously switching the engine off at a stop is probably minimaly contributing compared to those other factors!

I can understand turning off ones engine if your going to be stopped for a number of minutes but, in the past, we were always told that an engine burns more fuel on startup, especially when cold.

If, in Germany, you live in town and a minute after leaving home you hit your first traffic light, followed closely by others when your engine is still cold especially in North Germany.
How does what you describe help emissions? 🤔

This doesn't include stop start hybrid vehicle of course.
Since you mention Germany: https://www.motorhomefun.co.uk/foru...-down-of-your-moho-engine.309857/post-6314353
All that non eco driving behaviour will be creating huge demamds on parts chains as well & subsequent pollution etc.
So I drive to save fuel & wear & tear, thanks to my driving instructor!
 
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Fun fact. My performance car actually has an oil warmer. Coolant water has a heat exchanger with the oil. Water is pretty much always hotter than the oil...

Oil coolers (air/oil) exist of course but not on any normal production engine AFAIK.
I think you’ll find it’s a cooler, oil will run hotter than the cooled coolant returning from the radiator, under load in a performance car oil can run at 130’c without some help, here’s a fun fact every increase of 10’C over approx 90’C reduces the life of the oil by over 10% (average temperatures over the life of the oil)

Some performance engines have 2 or more cooling systems to cool the engine, oil and or intake charge, if your van has a water cooled EGR then it’s likely that it has its own cooling system with independent temperature control within the system that cools the engine.
 
Fun fact. My performance car actually has an oil warmer. Coolant water has a heat exchanger with the oil. Water is pretty much always hotter than the oil...

Oil coolers (air/oil) exist of course but not on any normal production engine AFAIK.

They are standard on numerous production cars! ✔️

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