Warming up an engine

UK PROFESSIONAL DRIVERS FORUMS THE UK PROFESSIONAL DRIVERS FORUM (INTERACTIVE)
81

Carryfast:

Rjan:

Rjan:
Cold engines also have looser tolerances, which is why the oil should be relatively thicker at cold than it would be with everything at operating temperature.

Just to correct myself, I’ve got this the wrong way around - no engine ever got tighter with heat applied! :laughing:

But the principle still stands: that multi-viscosity oils are basically specified to be suited to the lubrication requirements of the engine both hot and cold.

Oil that is modestly thicker when cold does not necessarily starve any surfaces of lubrication.

Mass-production engines would not be designed nowadays with surfaces that couldn’t be lubricated for an appreciable number of minutes while the oil heated, because the amount of friction wear would be rampant.

To a point, thicker oil simply increases mechanical resistance (whist still providing adequate lubrication), which if anything generates heat and helps to warm the oil which can only be a desirable effect in this situation.

That is why the manufacturers advice is to give the oil a few seconds to circulate and pressurise, but no more.

It’s clear that the least possible demand on the oil to seperate the moving parts of an engine is when it’s idling not under any load.Also bearing in mind that there is a difference between engine speed ( high idle ) as opposed to ‘load’.The oil cooler and water thermostats are what gets the engine up to temperature while a vehicle that isn’t moving obviously applies less cooling effect to the radiators as they open thereby providing a marginal reduction in the time needed to get the oil and water up to their optimum operating temps.Although having said that modern synthetic oil obviously changes things to a point but viscosity is still more about the fact that it needs to seperate fast moving parts under high load while providing optimum circulation at low temps.Bearing in mind that engine tolerances definitely close up at working temperature while synthetic oils can go up to 60 grade when hot.Which proves that they are designed to provide maximum protection at working temperature.IE putting an engine under any type of considerable load at low temperatures means that the oil will be at its weakest ( as low as 5-15 grade ) because at those temperatures it’s designed for circulation not protection. :bulb:

As for supercharged piston aircraft.By FD’s logic they’d have just fired her up taxied out and took off ?.In which case I’d prefer nmm to be the pilot if we’re going out on a raid over Germany.While we’ll put you on the list as tail gunner so you’re as far away from the cockpit as possible. :smiling_imp: :laughing:

youtube.com/watch?v=4xRbQZrpG1w

Er, ok :unamused: :laughing: By my logic?? As in, I just came up with this :unamused: ? These were low level maritime patrol aircraft for the coastguard as well as turbine types. Not some Sunday jaunt in an Austin allegro. It was standard operating procedures. I think the fleets written procedures on how to operate our particular turbine and super charged aircraft were a little more robust than your opinion. I did not say we “fired them up” and took off. I said we limited operating the supercharged piston engines at excess idle.

82

Carryfast:
As for supercharged piston aircraft.By FD’s logic they’d have just fired her up taxied out and took off ?.In which case I’d prefer nmm to be the pilot if we’re going out on a raid over Germany.While we’ll put you on the list as tail gunner so you’re as far away from the cockpit as possible. :smiling_imp: :laughing:

youtube.com/watch?v=4xRbQZrpG1w

There is a slight difference between what happens next to the aircraft engine and what most of people have said about warming up a truck engine.

My understanding of aircraft is you don’t tend to bimble gently down the runway and meander into the sky with the engine just above tick over.
Excpet maybe for this aircraft, but I have a feeling that his engine weren’t on idle… :laughing:

Even the gliders I flew we made sure we had the engine nicely warmed up and hang the fuel cost. :laughing:

83

Hang about, I always thought it was the other mondo who was a ships captain? Have I had that the wrong way around? : [emoji38] :astonished:
[/quote]
You mean there’s two of them! God help us all lol

/quote]

I think there’s a Ray and there’s Roy. I can never remember who’s who :smiley:
[/quote]

[/quote]

[/quote]
That makes two of us then! I did cover my arse though, ship’s captain or a lorry driver, so I’m covered both ways.

I am the one that drive a boat for me sins … and i never commented because all I know is that oil is needed :slight_smile:

84

Carryfast:

newmercman:
If you’ve ever tried to pour oil from a can at low temperatures, you’ll know exactly why you should let it warm up before you force it around an engine.

It’s all counter intuitive in that we expect oil to be all thick and like tar at low temperatures which would probably be the case 'if it was single grade not multi grade let alone modern synthetics.In which case it’s optimum viscosity is when the engine is at optimum working temperature and all tolerances at their minimum.

IE it’s best to let the engine warm up under as little load as possible because at low temps the oil is designed for optimum circulation and optimum protection under load at working temperature. :bulb:

I’m not sure I’m aware of what the difference is between optimum protection and optimum circulation.

85

Freight Dog:
Er, ok :unamused: :laughing: By my logic?? As in, I just came up with this :unamused: ? These were low level maritime patrol aircraft for the coastguard as well as turbine types. Not some Sunday jaunt in an Austin allegro.I did not say we “fired them up” and took off. I said we limited operating the supercharged piston engines at excess idle.

Apologies if you took it as a flippant remark that wasn’t how it was intended.

However I don’t get your point.So are you agreeing with the idea of reducing engine load to the absolute minimum,which realistically means idle or high idle,until the engine has reached at least a decent water temperature,before putting it under any considerable load ?. :confused: Which is how I read nmm’s comments and was always how I treated someone’s truck,if not always my own car.That applies whether it’s a car or a truck or a Lancaster ?.While no one is suggesting ‘excessive idling’ in that. :confused:

Although having said that in severe weather it’s been well known that truck engines have been left to idle over night.Sometimes to the point of not being shut down over periods of weeks,let alone days,without it affecting durability in any noticeable way and certainly better than the alternative of shutting it down when it would have been better left running.

86

just out of interest a CAT C15 in a new truck (to me) froze up overnight due to Paccar dealer not checking the oil plug in heater worked at service time . anyway the fitters came out tented up engine big gas heater blowing onto engine until it drained out,they then heated up the oil a bit more (changed filters) and put back in.Well by then I was half a day late leaving but the fitters insisted I did not move until the engine oil temp gauge was up to spec(cant remember the temp).On asking they told me to never move when starting just idle engine till oil temp got to range.

87

A couple of years ago I wrote a 3000 word feature on engine oils, that’s a lot of words, with a couple of adverts it was a 6 page deal. In order to do that there was a lot of research involved. To condense that article into layman’s terms, oil is used to lubricate, cool and hold contaminants in suspension to prevent engine wear and that’s it really.

Synthetic oils are not really synthetic, it’s the same dinosaur juice as mineral oil, but the hydrocarbon chain is altered, think of oil as spaghetti, synthetics are like the uncooked version, the hydrocarbon chains are all in nice straight lines, mineral oil is like Spaghetti after it’s been cooked and stirred, the hydrocarbons are a jumbled mess.

This is what gives synthetic oils their lower viscosity and that is important with a modern engine, manufacturing tolerances are extremely tight, so a thinner oil is required, because of EGR and DPF contaminants are increased and a thinner oil is necessary to avoid increasing viscosity to the point that your oil turns into grinding paste.

So taking all of that into account, a modern engine doesn’t need to be warned up for lubrication purposes, however my CAT is not a modern engine and I run it on 15W40, Chevron Delo, I use the 5W30 synthetic version in the Volvo. So in theory the Volvo could be a start and go truck, however it’s not that simple, there’s a lot of wiring inside an engine and sensors monitoring all kinds of stuff, as well as many plastic components, I prefer to let those come up to temperature gradually rather than a sudden shock load, plus my operation is a little bit more extreme than many, at the weights I run (up to 63.5ton) there’s no such thing as a gentle warm up, the engine is working hard the second you engage the clutch.

Sent from my SM-G930W8 using Tapatalk

88

Carryfast:

Freight Dog:
Er, ok :unamused: :laughing: By my logic?? As in, I just came up with this :unamused: ? These were low level maritime patrol aircraft for the coastguard as well as turbine types. Not some Sunday jaunt in an Austin allegro.I did not say we “fired them up” and took off. I said we limited operating the supercharged piston engines at excess idle.

Apologies if you took it as a flippant remark that wasn’t how it was intended.

However I don’t get your point.So are you agreeing with the idea of reducing engine load to the absolute minimum,which realistically means idle or high idle,until the engine has reached at least a decent water temperature,before putting it under any considerable load ?. :confused: Which is how I read nmm’s comments and was always how I treated someone’s truck,if not always my own car.That applies whether it’s a car or a truck or a Lancaster ?.While no one is suggesting ‘excessive idling’ in that. :confused:

Although having said that in severe weather it’s been well known that truck engines have been left to idle over night.Sometimes to the point of not being shut down over periods of weeks,let alone days,without it affecting durability in any noticeable way and certainly better than the alternative of shutting it down when it would have been better left running.

It’s not a point. It’s just what we did. We followed the SOPs. We didn’t idle the engines excessively. The aircraft were run on the ground at a set rpm. The only time idle was selected prior to TO was during start itself and to to check the idle value once warmed up.

Re truck engine side I’m saying the same thing. Essentially If you wanted to follow the procedure laid down in the lorry handbook, most cases they seem to say these days avoid warming up by idling.

No stress mate. If it was out of character I’d have presumed you were kidding so apology accepted/not needed as you were kidding :smiley:

89

muckles:

Carryfast:
As for supercharged piston aircraft.By FD’s logic they’d have just fired her up taxied out and took off ?.In which case I’d prefer nmm to be the pilot if we’re going out on a raid over Germany.While we’ll put you on the list as tail gunner so you’re as far away from the cockpit as possible. :smiling_imp: :laughing:

youtube.com/watch?v=4xRbQZrpG1w

There is a slight difference between what happens next to the aircraft engine and what most of people have said about warming up a truck engine.

My understanding of aircraft is you don’t tend to bimble gently down the runway and meander into the sky with the engine just above tick over.

Leaving a motorway services with a loaded 44 tonner accelerating up to a safe motorway merging speed among other possible similar scenarios ?.

90

Rjan:

Carryfast:

newmercman:
If you’ve ever tried to pour oil from a can at low temperatures, you’ll know exactly why you should let it warm up before you force it around an engine.

It’s all counter intuitive in that we expect oil to be all thick and like tar at low temperatures which would probably be the case 'if it was single grade not multi grade let alone modern synthetics.In which case it’s optimum viscosity is when the engine is at optimum working temperature and all tolerances at their minimum.

IE it’s best to let the engine warm up under as little load as possible because at low temps the oil is designed for optimum circulation and optimum protection under load at working temperature. :bulb:

I’m not sure I’m aware of what the difference is between optimum protection and optimum circulation.

Using the Lanc as an extreme example.IE needs a 100 grade engine oil at its normal running temp.So we bring that down to 15 grade to aid better circulation from cold.You’re saying we can now apply full load from cold with a 15 grade oil in an engine which needs 100 grade ?.

91

muckles:
Even the gliders I flew we made sure we had the engine nicely warmed up and hang the fuel cost. :laughing:

:laughing:

92

newmercman:
Synthetic oils are not really synthetic, it’s the same dinosaur juice as mineral oil, but the hydrocarbon chain is altered, think of oil as spaghetti, synthetics are like the uncooked version, the hydrocarbon chains are all in nice straight lines, mineral oil is like Spaghetti after it’s been cooked and stirred, the hydrocarbons are a jumbled mess.

I’d been led to believe that synthetics really were manufactured oils, in the sense they are chemically reformed from non-oil bases?

Analogous, but in the opposite way, to chemical cracking, where petrols and gases are not simply distilled or refined from crude, but are actually manufactured from heavier oils (and are “synthetic” in this respect).

This is what gives synthetic oils their lower viscosity and that is important with a modern engine, manufacturing tolerances are extremely tight, so a thinner oil is required, because of EGR and DPF contaminants are increased and a thinner oil is necessary to avoid increasing viscosity to the point that your oil turns into grinding paste.

If you needed merely a less viscous oil, wouldn’t you just use a lighter oil?

So taking all of that into account, a modern engine doesn’t need to be warned up for lubrication purposes, however my CAT is not a modern engine and I run it on 15W40, Chevron Delo, I use the 5W30 synthetic version in the Volvo. So in theory the Volvo could be a start and go truck, however it’s not that simple, there’s a lot of wiring inside an engine and sensors monitoring all kinds of stuff, as well as many plastic components, I prefer to let those come up to temperature gradually rather than a sudden shock load, plus my operation is a little bit more extreme than many, at the weights I run (up to 63.5ton) there’s no such thing as a gentle warm up, the engine is working hard the second you engage the clutch.

I would think the amount of mechanical load on an engine depends on much more than the weight it is pulling. It depends on the size and rated power of the engine itself, and the gear selected.

A powerful engine in a crawler gear can usually pull a full load at idle - the transmission may be begging for mercy, but the engine will not be. And let’s face it, nobody thinks to pre-heat the gearbox oil or the differential oil, or keep the vehicle crawling around the yard all night lest the gearbox go cold before the following morning’s journey, so why molly-coddle the engine, unless the load being hauled is so exceptionally large relative to the capability of the engine (or the gradient of the terrain so steep in the first few miles of the journey) that you’re going to be at full-throttle just to keep moving at a steady speed (and the best answer to that would usually be to invest in a bigger engine to begin with, not to waste good money on fuel by pre-heating it all the time).

93

Carryfast:

Rjan:

Carryfast:

newmercman:
If you’ve ever tried to pour oil from a can at low temperatures, you’ll know exactly why you should let it warm up before you force it around an engine.

It’s all counter intuitive in that we expect oil to be all thick and like tar at low temperatures which would probably be the case 'if it was single grade not multi grade let alone modern synthetics.In which case it’s optimum viscosity is when the engine is at optimum working temperature and all tolerances at their minimum.

IE it’s best to let the engine warm up under as little load as possible because at low temps the oil is designed for optimum circulation and optimum protection under load at working temperature. :bulb:

I’m not sure I’m aware of what the difference is between optimum protection and optimum circulation.

Using the Lanc as an extreme example.IE needs a 100 grade engine oil at its normal running temp.So we bring that down to 15 grade to aid better circulation from cold.You’re saying we can now apply full load from cold with a 15 grade oil in an engine which needs 100 grade ?.

Like a moth to a flame out of morbid curiosity I watched your vid :smiley:

You know the whole reason you posted that vid was after you read my post recollecting we didn’t run our piston engines at idle for excessive amounts of time? So, having confused this with meaning we opened the throttles up without warming, you post a vid. A vid intending to show another engine running at idle to warm up. (A different engine almost a grandmas lifetime apart, fitted to a different machine, but what the heck).

Well, you do know that Lanc would not be sitting at idle to warm up in that vid :laughing: ?

94

Rjan:

newmercman:
Synthetic oils are not really synthetic, it’s the same dinosaur juice as mineral oil, but the hydrocarbon chain is altered, think of oil as spaghetti, synthetics are like the uncooked version, the hydrocarbon chains are all in nice straight lines, mineral oil is like Spaghetti after it’s been cooked and stirred, the hydrocarbons are a jumbled mess.

I’d been led to believe that synthetics really were manufactured oils, in the sense they are chemically reformed from non-oil bases?

Analogous, but in the opposite way, to chemical cracking, where petrols and gases are not simply distilled or refined from crude, but are actually manufactured from heavier oils (and are “synthetic” in this respect).

This is what gives synthetic oils their lower viscosity and that is important with a modern engine, manufacturing tolerances are extremely tight, so a thinner oil is required, because of EGR and DPF contaminants are increased and a thinner oil is necessary to avoid increasing viscosity to the point that your oil turns into grinding paste.

If you needed merely a less viscous oil, wouldn’t you just use a lighter oil?

So taking all of that into account, a modern engine doesn’t need to be warned up for lubrication purposes, however my CAT is not a modern engine and I run it on 15W40, Chevron Delo, I use the 5W30 synthetic version in the Volvo. So in theory the Volvo could be a start and go truck, however it’s not that simple, there’s a lot of wiring inside an engine and sensors monitoring all kinds of stuff, as well as many plastic components, I prefer to let those come up to temperature gradually rather than a sudden shock load, plus my operation is a little bit more extreme than many, at the weights I run (up to 63.5ton) there’s no such thing as a gentle warm up, the engine is working hard the second you engage the clutch.

I would think the amount of mechanical load on an engine depends on much more than the weight it is pulling. It depends on the size and rated power of the engine itself, and the gear selected.

A powerful engine in a crawler gear can usually pull a full load at idle - the transmission may be begging for mercy, but the engine will not be. And let’s face it, nobody thinks to pre-heat the gearbox oil or the differential oil, or keep the vehicle crawling around the yard all night lest the gearbox go cold before the following morning’s journey, so why molly-coddle the engine, unless the load being hauled is so exceptionally large relative to the capability of the engine (or the gradient of the terrain so steep in the first few miles of the journey) that you’re going to be at full-throttle just to keep moving at a steady speed (and the best answer to that would usually be to invest in a bigger engine to begin with, not to waste good money on fuel by pre-heating it all the time).

Pulling a load in crawler at ‘idle’ isn’t going to work in the example of leaving a motorway services and accelerating up to speed to merge safely for example.

As for synthetic motor oils they seem to be one of the GTL formulas like GTL diesel fuel not a crude oil distillate ? and it’s their potential viscosity ‘range’ which is the clever bit.I use 10/60 in the Jag which again is all about the top figure IE miraculous oil pressure figures and obviously good protection levels under high load at the type of running temperatures which only an old school Jag V12 can create.The lower figure probably being inferior regarding actual protection at lower temperature to the old 20/50 grade stuff.But again that lower figure being all about getting it around the engine quickly from cold rather than the outright level of protection when it’s done it. :bulb:

95

Rjan:
I would think the amount of mechanical load on an engine depends on much more than the weight it is pulling. It depends on the size and rated power of the engine itself, and the gear selected.

A powerful engine in a crawler gear can usually pull a full load at idle - the transmission may be begging for mercy, but the engine will not be. And let’s face it, nobody thinks to pre-heat the gearbox oil or the differential oil, or keep the vehicle crawling around the yard all night lest the gearbox go cold before the following morning’s journey, so why molly-coddle the engine, unless the load being hauled is so exceptionally large relative to the capability of the engine (or the gradient of the terrain so steep in the first few miles of the journey) that you’re going to be at full-throttle just to keep moving at a steady speed (and the best answer to that would usually be to invest in a bigger engine to begin with, not to waste good money on fuel by pre-heating it all the time).

I had one of those 3over3 splitter things, wouldn’t go into 4th for at least the first 50 mile

96

Freight Dog:
Like a moth to a flame out of morbid curiosity I watched your vid :smiley:

You know the whole reason you posted that vid was after you read my post recollecting we didn’t run our piston engines at idle for excessive amounts of time? So, having confused this with meaning we opened the throttles up without warming, you post a vid. A vid intending to show another engine running at idle to warm up. (A different engine almost a grandmas lifetime apart, fitted to a different machine, but what the heck).

Well, you do know that Lanc would not be sitting at idle to warm up in that vid :laughing: ?

To be fair I might have taken a liberty with the supercharged piston brief. :wink:

We agree that it’s sitting there warming up ? and it’s not taxiing which then just leaves the question of the definition of idle.The engines certainly don’t look/sound like they are under a considerable,if any,load.Probably because just as it says they are being warmed up ready for taxi out and take off. :confused:

97

Rjan, weight is important in the real world, yes I could fire up my engine and get that 60tons + and the drag of 9axles moving without putting the engine under full load, however in the real world it would make me a hazard to other road users and take a similar time to letting it idle up to temperature and then driving normally.

I also run at high idle, up to 1000rpms, once the oil pressure drops to normal, the rpms go up. As I said, I have solid data from my oil samples that prove that I’m doing the right thing by my engines, my wear metals are low and oxidation and niration are almost non existent. A 15min warm up uses around 2litres of fuel, so approx 500litres annualy.

For me with two lorries that’s worth every penny, but for a company with 100 lorries that’s 50,000litres, 500 lorries and it’s 250,000litres, that’s a lot of money and if you’re running a 3yr replacement cycle, it doesn’t really matter if you take a bit of life out of the engine, it will be somebody else’s problem by then.

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98

Freight Dog:

muckles:
Even the gliders I flew we made sure we had the engine nicely warmed up and hang the fuel cost. [emoji38]

[emoji38]

Am I being a wee bit pedantic? Search for
“Self launch gliders”.

Sent from my GT-S7275R using Tapatalk

99

Franglais:

Freight Dog:

muckles:
Even the gliders I flew we made sure we had the engine nicely warmed up and hang the fuel cost. [emoji38]

[emoji38]

Am I being a wee bit pedantic? Search for
“Self launch gliders”.

Sent from my GT-S7275R using Tapatalk

You do get gliders with engines.

They’re called airplanes. :laughing:

Sorry terrible joke and probably technically wrong. :blush:
Here you go.

And he’s a really big one, didn’t catch on as glide ratio wasn’t much to write home about.

100

Franglais:

Freight Dog:

muckles:
Even the gliders I flew we made sure we had the engine nicely warmed up and hang the fuel cost. [emoji38]

[emoji38]

Am I being a wee bit pedantic? Search for
“Self launch gliders”.

Sent from my GT-S7275R using Tapatalk

No you’re dead right. I took it as a joke, made me laugh anyway :smiley: