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

I just take it easy from cold to let everything expand to where it needs to be. I don't worry too much about getting the turbo cooled as it never gets to extreme temperatures
 
Remember the old " Running in please pass" signs in the rear window of vehicles ? Always confused me as a kid....Having said that , modern production techniques and materials have vastly improved since then, reducing tolerances and therefore the expansion phase and the need for "running in" at all. So too has the film strength of synthetic lubricating oil , allowing much thinner oils to give greater protection, especially from cold start up, also making the first service at 1000/1500 miles obsolete . In terms of emissions , getting the catalyst up to operating temperature as quickly as possible is the aim nowadays , which means extended and unnecessary idling during warm up is not desirable. As for cooling down, the temperature tolerance of ( fully) synthetic oil and the use of Viton seals means the turbo and the oil within, can easily survive undamaged when engine is stopped.
 
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It appears that there are some on here that know more than the experts at Caterpillar. During my fifty years of operating diesel powered heavy earthmoving equipment I have never come across any engine manufacturer that didn't require a run down cooling period before stopping the engine. On a lot of sites if the operator stopped the engine without allowing it to run on tickover for 5 minutes he would get his marching orders. Even now with todays modern engines I let my vehicles idle for a few minutes before stopping them as I have seen the premature results of not doing so.
 
Whose recieved wisdom ? Where’s the evidence based research ?
This so far is purely anecdotal.
I’m open to facts ,
Interesting discussion tho 💡👍
My last Kia Carnival(sedona) along with the transit before both had large yellow stickers, on the sun visors +kia also had one on the door stating run the engine for 2 minutes after stopping before turning off.
I always allow mine to cool & usually just before arriving anywhere I try to drive 'off turbo' with no huge amounts of acceleration.Kia was water cooled but this transit isn't.
Those were the days when you would see people at fuel stations lifting the filling pipe to get the last drop out! :LOL:
I still do it & shake it.:LOL:
On tick over all the air is still and after a short time the cooling fan has to come on.
Both my rad fan & ac fan start up initially then run to full speed & then drop back to slow.& are then controlled by the engine temperature. If one fan does not start then the ac will compressor will never start.
 
If I was driving industrial machinery I would follow the manufacturers instructions. My Fiat instructions are.

“WARMING UP THE ENGINE JUST AFTER IT HAS STARTED Proceed as follows: drive off slowly, letting the engine turn at medium revs. Do not accelerate abruptly; do not demand full performance at first. Wait until the engine coolant temperature gauge starts moving.”

“SWITCHING OFF THE ENGINE Turn the ignition device to STOP with the engine idling.”

This is what I do.

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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!
You forgot “hot turbo still spinning with no oil being pumped to its bearings”🤣🤣🤣🤣🤣😁😁👍

Each one to their own!
There’s two sets of drivers in all walks of life
1, mechanically sympathetic
2, NON mechanically sympathetic
 
Some of these replies really do make me chuckle; there is a distinct lack of basic mechanical knowledge. 🤪

You must be having a right laugh at me, then, because I have almost zero mechanical knowledge. We can't all know everything. And just because I have owned many vehicles doesn't mean I should be knowledgable about them, just as I know nothing about my home plumbing or electrics :)

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It appears that there are some on here that know more than the experts at Caterpillar. During my fifty years of operating diesel powered heavy earthmoving equipment I have never come across any engine manufacturer that didn't require a run down cooling period before stopping the engine. On a lot of sites if the operator stopped the engine without allowing it to run on tickover for 5 minutes he would get his marching orders. Even now with todays modern engines I let my vehicles idle for a few minutes before stopping them as I have seen the premature results
Makes a mockery of the modern stop/start engines then ....
 
It seems to me most motorhomes sit for at least 5 minutes withe engine running before moving off!!. Particularly annoyingly if they are parked up next to you. Goodness knows why they can't set the sat nav, put seat belt on, pick their nose etc before starting the engine. And why start it before the wife has even finished doing the washing up? :rolleyes:

As for after - I will allow my high performance turbo charged sports car engine to idle a little after a high speed run just to allow the turbo to cool a little but a bit unnecessary in a motorhome.

My husband does this in every vehicle he drives and it annoys the sh*t out of me. Example.......we get in and he starts the engine. Then realises he's left something in the house that he needs, so he goes to get it. Gets back in and starts to set the satnav. Starts driving out of the drive and then decides to put his seatbelt on, while the car is weaving around on the road. Honestly, it drives me nuts!!!
 
Back in the seventies I worked on turbocharged Bell 47 helicopters. You could see the turbocharger glowing red hot as it came into the hover before landing on it's skids. That hover requires a high level of power. Pilots always observed a three minute run down to cool the turbo so oil did not bake in the small oil passages. Fixed wing aircraft land on the runway and taxi in, this low power period cools the turbo so less need for an extended run down. Even if you thrash down the motorway you will still slow down before turning off and driving to a parking spot, so a long cooling period not needed.
 
It appears that there are some on here that know more than the experts at Caterpillar. During my fifty years of operating diesel powered heavy earthmoving equipment I have never come across any engine manufacturer that didn't require a run down cooling period before stopping the engine. On a lot of sites if the operator stopped the engine without allowing it to run on tickover for 5 minutes he would get his marching orders. Even now with todays modern engines I let my vehicles idle for a few minutes before stopping them as I have seen the premature results of not doing so.
Plant engines that operate in a very narrow rev range and are pretty static are a different beast to Moho engines that have a much wider rev range and have to operate at a much greater speed range
 
I had Ford Cosworths in the 90's and after a motorway run, then slow drive 3 miles to home I used to let the engine idle for a minute or two to cool to allow the Garret Turbo to cool down whilst still circulating oil. It could often be seen to be glowing Red Hot under the bonnet, but the cooling fan would kick in and sometimes run for 5/10 minutes after walking away before the Turbo was deemed cool enough by the thermostat. It was mentioned in the Car Owner Manual to always let the engine idle to cool the turbo after a run, so I always tried to do this....if I had the time.;)

The Van however is a modern diesel with lower engine revs and a smaller Turbo so I don't have to think about letting it idle and cool down so much, if the fan kicks in after stopping then its probably half way through doing a Regen to clear The DPF which doesn't happen that often when shutting the engine down thus far.
Good point on mentioning the Stop/Start on modern vans, that somehow contradicts the idea of letting the engine idle for an extended time before shut down, then again maybe it knows when to allow the stop/start function, I know our car does.
LES

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I'd have thought the engine will get even hotter on tick over after a run, while driving the radiator and whole engine is being cooled by a fast air flow. On tick over all the air is still and after a short time the cooling fan has to come on.

My motorcycle has a water temperature display and you can see it happening, in traffic the water temperature will climb to 103°c and the fan comes on (switches off about 95😉)
My 1989 T25D VW Westfalia California has an auxiliary water pump under the bonnet and if the engine is too hot, it will keep the radiator water circulating and fan blowing untill cool.
With modern, thinner synthetic oils, old practices need less adherence although I still let my engine run for a short time to allow oil to circulate through the turbo after a run out. 🤔
 
I worked in a stable years ago-as a teenager-we had an old horse box lorry and that was started up and left to run for a while. Not something to do now with modern engines.
It was an old TK and this was in the winter weather, frosty, and cold with the old dung heap steaming gently, fantastic days!
In the winter, old horse boxes vehicles should always be parked over or near the manure heap where the heat from the manure will help stop the frost.

That's what we used to do on our farm in the UK.
 
Some of these replies really do make me chuckle; there is a distinct lack of basic mechanical knowledge. 🤪

My post above was not aimed at anyone specifically, more an observation. WESTY66 posting about cool down periods on heavy plant is the point I was getting at. Mechanical sympathy cost very little time and has a huge impact on longevity and reliability.

An engine, be it ‘modern’ or classic, high performance or more mundane, diesel or petrol, all benefit from a little care with a steady warm up and a cool down commensurate to recent use…. It’s just good practice. ✔️

WRT to starting and not pulling off immediately, I’m guilty as charged. I. need to raise the leveller's and air up the bags, so it takes a minute or two. I also follow good practice of doing a vehicle walk around and visual assessment/inspection whilst doing this; just to check everything is as it should be. Again, just good practice and gives you the confidence to pull away with everything in order. ✔️

WRT running in, it is still a thing. All four of my daily driver cars for the last twelve years, until I stopped work, had a mandatory running in service to change oil and check vehicle at 1200 miles. ✔️
 
It appears that there are some on here that know more than the experts at Caterpillar. During my fifty years of operating diesel powered heavy earthmoving equipment I have never come across any engine manufacturer that didn't require a run down cooling period before stopping the engine. On a lot of sites if the operator stopped the engine without allowing it to run on tickover for 5 minutes he would get his marching orders. Even now with todays modern engines I let my vehicles idle for a few minutes before stopping them as I have seen the premature results of not doing so.

50yrs ago, the big Cat bulldozer and plant that I repaired had a mineral oiled petrol donkey engines that you HAD to start in order warm up the circulating water to the main before using the donkey engine to start the detergent oiled main engine. 🤔
 
My husband does this in every vehicle he drives and it annoys the sh*t out of me. Example.......we get in and he starts the engine. Then realises he's left something in the house that he needs, so he goes to get it. Gets back in and starts to set the satnav. Starts driving out of the drive and then decides to put his seatbelt on, while the car is weaving around on the road. Honestly, it drives me nuts!!!

Sack him! 😄
 
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You must be having a right laugh at me, then, because I have almost zero mechanical knowledge. We can't all know everything. And just because I have owned many vehicles doesn't mean I should be knowledgable about them, just as I know nothing about my home plumbing or electrics :)

See post #48
 
Plant engines that operate in a very narrow rev range and are pretty static are a different beast to Moho engines that have a much wider rev range and have to operate at a much greater speed range
Not sure I'd agree with that, most of my driving is between 2000-3500rpm? 🤔
 
No as stop:start only operates when appropriate. It doesn’t function until the engine is warm and if the engine is too hot it won’t work either.
Too hot ??? Most engines are able to regulate their temperature nowadays , I've driven and been involved with stop/start vehicles since their inception and never experienced a "too hot " scenario. Most vehicles are fitted with a coolant to oil heat exchanger and performance engines also have additional oil coolers. Too hot would indicate a malfunction of some kind.

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Too hot ??? Most engines are able to regulate their temperature nowadays , I've driven and been involved with stop/start vehicles since their inception and never experienced a "too hot " scenario.
I think that was explained in post #51.
 
Too hot ??? Most engines are able to regulate their temperature nowadays , I've driven and been involved with stop/start vehicles since their inception and never experienced a "too hot " scenario. Most vehicles are fitted with a coolant to oil heat exchanger and performance engines also have additional oil coolers. Too hot would indicate a malfunction of some kind.
The times ours doesn't use start stop are when cold and when regenerating and the idle speed then increases to get the engine warm. If people make a habit of driving around at 4000 rpm I suppose the turbo could get hot enough to require a cooling down period and the car would probably sense that on the stop start but I've never experienced it. As on most journeys we probably have multiple engine stops on stop start and the engine shows no sign of wear at 108k miles is still on the first battery and clutch I think things have moved on a bit on running in warming and cooling.
 
Around year 2000.
2.8 JTD Fiat engines and gearboxes had a bodged 5th gear fitted on top of the regular 4 speed box.
This was prone to failure due to poor lubrication.
The advice was to not use 5th gear until the engine was warm and the oil flowed more freely.

Advances in oil performance over the last 20+ years may have reduced the risk.
 
Good point on mentioning the Stop/Start on modern vans, that somehow contradicts the idea of letting the engine idle for an extended time before shut down,
But if it lasts 12 months the manufacturer is happy They only have to comply with emissions requirements .If it fails that is the owners problem at at his cost
 
Modern stop start farce isn’t there to make your engine last. It’s there as BS and apparently low emissions.

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