Leave the diesel running??

Submitted: Sunday, May 20, 2012 at 22:59
ThreadID: 95699 Views:8893 Replies:18 FollowUps:33
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Hi all,

I've always owned petrol vehicles and the Landcruiser is my first Diesel motor. I'm loving it but wouldn't mind getting something cleared up. Is it true that it's better to leave a diesel engine running if you only intend to be way from your car for a short period of time? example......ducking into the bottle shop while the Mrs is in the car...switch it off or leave it on? I can't remember where I heard it but apparently it's better to leave the engine on rather than turn it off/on again after a short spell? Myth or Fact?
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Reply By: Member - nick b - Sunday, May 20, 2012 at 23:20

Sunday, May 20, 2012 at 23:20
Cruiser , I switch off @ $ 1.50 plus a litre .

Leaving diesel running might relate more to trucks etc

But all engine will last longer if there not turned off .......heating & cooling thingo

cheers nick
Cheers Nick b
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Reply By: Member - Joe n Mel n kids (FNQ - Monday, May 21, 2012 at 00:08

Monday, May 21, 2012 at 00:08
leave it running, millions for and against but really the most damage is done in the first few seconds after start up and on the first rev there is practally NO OIL PRESSURE ...... and that equates to wear, fuel is cheap compaired to rebuilding eh ...... up here it is alway hot so we dont turn off unless we need to as ac is running always and also a deisel needs to be run at idle for a few mins not seconds to cool down properly ...............
Cheers
Joe
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Follow Up By: Member - Cruiser74 - Monday, May 21, 2012 at 02:52

Monday, May 21, 2012 at 02:52
G'day Joe (and co!) thanks for the response!
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Follow Up By: get outmore - Monday, May 21, 2012 at 16:41

Monday, May 21, 2012 at 16:41
Not actually so. The engine retains most of its oil for a fair while after being shut down. Check your dipstick from dead cold and after its been shut down for 10 minutes. Theres about a litre difference.

While cold starts might make very long term differences in motor longevity. Warm starts wouldn't make any appreciable difference
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Follow Up By: fisho64 - Monday, May 21, 2012 at 21:58

Monday, May 21, 2012 at 21:58
Joe-the "let it cool down" thing is really only if you've been working it hard, and its a turbo. Really, even if you've been cranking up the highway towing and then slow down in town and into a fuel station, its enough to let the turbo rpm slow down and cool a little.

Get Outmore-as a point of interest, a few weeks back I did the valve clearances on my 4 stroke outboard. It hadnt been run for 6 weeks and I was suprized to see oil droplets still on the cam lobes not yet dripped away. The litre difference would not appear to be what is on the machined surfaces, but merely what is in suspension around the engine, sprayed and running down the crankcase walls
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Reply By: graham B9 - Monday, May 21, 2012 at 06:31

Monday, May 21, 2012 at 06:31
Hi Cruiser 74

Don't belieive everything you read on this forum.

The reason is that the turbo in modern diesel engines spins at a ration of the engine revs. That being the case it is constantly increasing and decreasing in revs much greater than the engine revs. Hence it gets very hot.

Once you turn off your engine it takes time for the turbo to cool. If very hot it has a greater chance of ceasing. Letting the engine idle after running give the turbo time to cool down before being turned off. Many modern diesels have a "turbo timer" built in. This will spin the turbo or keep the engine running for a few minutes after you turn off the engine. Once it has cooled below a certain leve the engine/ tubo will switch off.

You can buy a after market turbo timer and have it fitted to your cruiser. Then you just switch off and walk away even though your engine is still running.
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Follow Up By: Member - Rod N (QLD) - Monday, May 21, 2012 at 10:59

Monday, May 21, 2012 at 10:59
I think it is illegal to leave the engine running and walk away in some states. If a timer is required then why isn't one fitted as standard? The cynics will say no timer will boost the coffers of repairers.
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Follow Up By: fisho64 - Monday, May 21, 2012 at 22:08

Monday, May 21, 2012 at 22:08
"Many modern diesels have a "turbo timer" built in."
personally I dont know of any at all? Thats not to say there arent but I have never seen a factory one?
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Follow Up By: Begaboy - Tuesday, May 22, 2012 at 08:57

Tuesday, May 22, 2012 at 08:57
Yes illegal to leave a running vehicle unattended - if something like hand brake does not work and truck rolls away and hurts someone ... your in BIG trouble -- and not worth saving those few $$ ( manual cars )

turbos are only super hot when you have been towing for a prolonged time under heavy load OR been running highway speed then suddenly STOP - these are the times you need to wait a min to allow to cool - if you just stop start from one red light to next then pull into coles car park - its not needed

I have had 4 separate diesels now - none with turbo timers - allow to cool after HEAVY TOWING but dont bother after short stop start city drive - NEVER had a turbo prob in ANY of the cars - and after 400K combined between all cars - you would think if this was an ISSUE with ALL diesels , i would have had a prob by now

Turbo timers ... pft about as essential as a HYCLONE or a teenagers 4 cylinder datsun with a blow off valve
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Follow Up By: Mapesy (QLD) - Saturday, May 26, 2012 at 13:18

Saturday, May 26, 2012 at 13:18
Agree entirely with you Begaboy. Unless the turbo has been working hard e.g towing, highway speeds etc. there is no real need to leave the engine running to ow the turbo to cool. I understood that switching off a motor with a hot turbo would stop oil lubricating the turbo whilst still running.
The issue of legallity is also correct I believe.
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Reply By: olcoolone - Monday, May 21, 2012 at 08:23

Monday, May 21, 2012 at 08:23
Mate do what you want, either way it's not going to hurt and as for wear at startup you won't notice any extra wear, the oil film left on moving parts is enough to stop any wear unless you start it up with you foot to the floor..... after a few second your engine will have all the oil it needs, but then again buy the time it reached damaging Rpm and load conditions it will have oil pressure.

Bit of an urban myth!

I think this myth came about in the old days when it was a chore to restart an engine.... people would leave them running.

This is myth could also go with the "let the engine warm up before driving".
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Follow Up By: Nomadic Navara - Monday, May 21, 2012 at 15:53

Monday, May 21, 2012 at 15:53
Quote "This is myth could also go with the "let the engine warm up before driving". "

The Engine Oil Bible says it does more harm to an engine to let it warm up on idle than moving off gently after the oil pressure comes up.

My Nissan D40 HB states that "If the engine has been operating at high rpm for an extended period of time, let it idle for a few minutes prior to shutdown." After a long stint of towing I generally run the last few kilometers at a rather relaxed manner.
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Follow Up By: olcoolone - Monday, May 21, 2012 at 16:35

Monday, May 21, 2012 at 16:35
You should always let any engine run with no load if the engine has been under load for an extended time...... like don't do an 10 kilometre climb up a big hill at maximum weight in 3rd gear and then get to the top of the hill and turn it straight off as soon as you have lifted your right foot.

But for 99.9% of driving and towing (unless into a 40 knot head wind on a 40 Deg day) you can turn it off as soon as you have come to a stop.

Most owner manuals have stuff in then for the .0001% situations.

Re idle warm up...... your spot on but with modern oils, coatings and materials you could run an engine to redline when cold and it would make very little difference in reliability or longevity.
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Follow Up By: Member - Mark (Tamworth NSW) - Monday, May 21, 2012 at 20:54

Monday, May 21, 2012 at 20:54
ocoolone

A question regarding engines run hot and hard then shut down.

A couple of times in 38-40C temperatures I have pulled our 1T camper trailer out of very steep gorge country (700m climb on narrow rough track with erosion check banks & hair pin bends over about 3-4km) with a petrol Pajero, when the Temp guage got to a stage which said "STOP". My friend had a diesel Jackaroo, he had same problem.
Should we have just left it idling with bonnet up rather than shutting it down?

Like to know for next time it happens.

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Follow Up By: fisho64 - Monday, May 21, 2012 at 22:25

Monday, May 21, 2012 at 22:25
Mark-unless either there was no coolant left, fan not working or an obvious similar fault, you should let it idle to cool down in that situation. The coolant will be still moving and drawing heat away from the cylinder head.
Stopping it immediately would take it a lot longer to cool down amongst other possible probs.
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Follow Up By: Ross M - Monday, May 21, 2012 at 22:36

Monday, May 21, 2012 at 22:36
Olcoolone.
If you don't gently drive while the engine is warming up, especially on aluminium cylinder head engines you will shorten the life of the head gasket.
With an aluminium head it isn't fully tight until the head has expanded to full size and this increases the clamp force at the gasket face. If given the berries when cold you are developing maximum cylinder pressures but the head is at it's loosest an very likely to develop leakage track lines across the sealing face.
Revving and loading an engine before it is hot is a really dumb thing to do.
If you believe as stated "you could run an engine to redline when cold and it would make very little difference in reliability or longevity" It doesn't indicate a sound knowledge of or regard for machinery.

When stopping the engine if it is "hot" only the uninformed or the rich shut em off straight away.
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Follow Up By: fisho64 - Monday, May 21, 2012 at 23:39

Monday, May 21, 2012 at 23:39
Ross-while I believe its foolish to flog an engine when cold, I have never heard of the aluminium head theory? While I know that aluminium expands and contracts more than cast iron, head bolts also both lengthen and lose some elasticity under increased temperature. Id expect that the loads would be somewhat similar overall? If it was the other way as you say then under more and more heat the head gasket would be tighter and tighter and hence LESS likely to fail under overheating when in fact this is usually when a head gasket fails?
However its not a bad way to look at it anyway.
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Follow Up By: olcoolone - Tuesday, May 22, 2012 at 08:19

Tuesday, May 22, 2012 at 08:19
Calm down Ross.

"Revving and loading an engine before it is hot is a really dumb thing to do.
If you believe as stated "you could run an engine to redline when cold and it would make very little difference in reliability or longevity" It doesn't indicate a sound knowledge of or regard for machinery. ""

Ross it was used as a hypothetical answer and if you could not see that then well!!!!!

I am not even going to respond to your stupid assumption about hot and cold and my mechanical capacity.

But I will respond to your other outrageous comment about alloy cylinder heads when cold.

Sure alloy expands but not to the degree you think it does especially at 95 Deg C., SOoooo does that mean on an turbo diesel engine with 16:1 compression ratio you should not even hit boost as it may blow the gasket?

Please provide data to back you claims of the difference in longevity and reliability of running an engine cold vs hot and maybe some data about shutting an engine off when hot (I am not talking about boiling).

Please be gentle with me, as you said "It doesn't indicate a sound knowledge of or regard for machinery" I'm not that smart when it comes to machinery but I am a good lover and I cook a mean blanquette de veau.



Buy the way I'm with Fisho on this re cold engines and why would you want to race a 4x4 engine anyway especially when cold....... perhaps it's the "new baby" syndrome..... can't do this and can't do that because..... then only to find out there are pretty robust and eating dirt and flies won't cause damage.

You have to laugh and smile some times and this is one of these moments.
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Follow Up By: Member - Michael J (SA) - Wednesday, May 23, 2012 at 12:00

Wednesday, May 23, 2012 at 12:00
"I am a good lover and I cook a mean blanquette de veau."

Hmmm, guess it doesn't hurt to advertise Richard... lol


MJ

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Reply By: Cravenhaven - Monday, May 21, 2012 at 08:59

Monday, May 21, 2012 at 08:59
Just to add to the comments re the turbo. If you have been driving hard in the minutes before stopping then it is prudent to leave the engine idling to allow the Turbo to spin down because as soon as you switch the engine off you lose all oil pressure and the turbos spin at incredible revs. If on the other hand you have been idling around the car park trying to find a spot then it is probably ok to just switch it off.
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Follow Up By: olcoolone - Monday, May 21, 2012 at 09:43

Monday, May 21, 2012 at 09:43
A turbo will slow down as soon as you lift your foot of the go pedal..... after a few seconds the turbo is off boost and at idle the turbo is still spinning but at a speed that doesn't generate heat.

The idea of letting a turbo cool down was for the bearings and the dispersion of heat, with modern turbo's of the last 15 years you can turn the engine of straight away with no damage.

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Reply By: Hairs & Fysh - Monday, May 21, 2012 at 09:52

Monday, May 21, 2012 at 09:52
Hi Cruiser74,
I leave my 1HD-T running, the fuel used at idle is buggar all, it's not going to do your pocket any harm or your Cruiser.
keeps everything ticking over, if it's a hot day the family are happier if the AC is still going, I know I hate sitting in a hot vehicle waiting.
Have a good one.



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Reply By: Allan B (Member, SunCoast) - Monday, May 21, 2012 at 10:55

Monday, May 21, 2012 at 10:55
I understand that the concept of leaving the engine idle until next needed came from the olden days to avoid using the starter motor unnecessarily.

The problem comes about due to the effect of electrons moving through the copper cables and windings of the starter motor at the high Ah's. These electrons move at incredible speed and tend to want to travel in a straight line so at every bend in the wire the electrons impinge on the outer side of the cable and the friction creates both heat and molecular wear. So the less the starter motor is used the better. The escaping electrons often lodge in the cooling system and cause radiator corrosion.

The problem is greater in cars manufactured before 1995 when a scientific breakthrough enabled wires to be manufactured with oxygen-free copper which significantly reduced the friction and enabled the electrons to move at much greater speed through the wires. The later addition of molybdenum produced even greater gains and there is current research into electroplating the wire strands with kryptonite.

There seems to be little evidence yet to support the benefit of utilising a HiClone device in the starter cable to realign the electrons but research continues by individuals into this.



Cheers
Allan

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Follow Up By: Fred G NSW - Monday, May 21, 2012 at 11:25

Monday, May 21, 2012 at 11:25
ROTFLMAO........
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Follow Up By: Member - Tony V (NSW) - Monday, May 21, 2012 at 11:37

Monday, May 21, 2012 at 11:37
Classic... lol
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Follow Up By: olcoolone - Monday, May 21, 2012 at 12:02

Monday, May 21, 2012 at 12:02
I always thought it came from the days of the horse and cart........ they found when you killed the engine it was imposable to get the Clydesdale running again.... old habits are hard to kill.
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Follow Up By: Member - MUZBRY(Vic) - Monday, May 21, 2012 at 12:23

Monday, May 21, 2012 at 12:23
Gday olcoolone
The main problem with the clydesdales was they had a bad earth strap and welded themselves to the ground if left to long. One had to fit a nose bag , and that reduced the amount of earth in the front and increased the amount of earth at the rear.

Muzbry
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Follow Up By: Mark , G - Monday, May 21, 2012 at 12:55

Monday, May 21, 2012 at 12:55
Muz.
i see your still on your medication..............keep them going for our sake :-P

ps.........we need another camping trip with little Wes and yourself ;-)
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Follow Up By: Member - barry F (NSW) - Monday, May 21, 2012 at 17:49

Monday, May 21, 2012 at 17:49
Well there ya go!! You learn something new every day! Thanks heaps Allan for that very comprehensive explanation as to the technology that goes with modern day vehicles. LOL
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Follow Up By: Member - MUZBRY(Vic) - Monday, May 21, 2012 at 20:11

Monday, May 21, 2012 at 20:11
Gday Mark
I'll see what I can do about a trip. Where would you like to go?

Muzbry
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Follow Up By: blown4by - Saturday, May 26, 2012 at 17:56

Saturday, May 26, 2012 at 17:56
Very helpful!
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Reply By: Member - Tony V (NSW) - Monday, May 21, 2012 at 13:29

Monday, May 21, 2012 at 13:29
Hmmm,

I am not a diesel owner and had a good laugh at some of the responses.

I decided to have a look through Google and the answer is TURN IT OFF.

But its not that easy... this is what I have found....

The reasons for leaving it running originated in a high compression engine and poor battery and recharging technology back in the 50's to early 80's.

Hard to start when cold, glow plugs to warm the cylinders pre start, sucked power from batteries that did not charge as well as modern batteries do now with alternators instead of Dynamo's.

So delivery trucks and others did not turn the engines off with, stop - starts as the batteries would not keep up with the start load.

The "spin down time" for Turbo's is valid, but 5 minutes???

BMW - Volkswagon and many, many European high powered turbo diesels have Stop Start technology, that kills the engine at traffic lights or when the engine is not needed.

Even Detroit state turn it off.

The start up wear is a myth, modern oils prevent this assumed wear, provided that they are changed regularly. If you don't change oil regularly, then the alleged idle wear is going to be 100 times worse..... :)

FACT: A diesel engine works best under load... which is why trucks use them.

FACT: A diesel engine at idle (no load) creates incomplete combustion, leading to carbon build up on valves, in the crankcase oil,in the combustion chamber, causing piston rings to wear. This is why Diesels need more frequent oil changes. Deposits in the engine oil cause wear.

That carbon is often seen after a down hill decent where the throttle is used lightly, the first dab on the throttle produces smoke, burning the excess carbon.

So the real answer is a mix of common sense.

Drive hard, give the engine a few minutes to let the turbo spin down.

Low speed driving, including much of the 4WDing, much done at low speed, you can turn it off as the low speed of the turbo won't matter, but, that is if you are not going to restart in a few minutes.


Just don't leave the engine running if the police are around.....




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Reply By: SDG - Monday, May 21, 2012 at 16:14

Monday, May 21, 2012 at 16:14
Years ago I use to deliver pizza.

I found that if I left the car running at each delivery, I used less fuel than if I turned it on and off at each time.
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Reply By: Rockape - Monday, May 21, 2012 at 18:17

Monday, May 21, 2012 at 18:17
Hi mate,
If you read the pooperating manual for most machines it will state for you to leave the engine idle down for between 3 and 5 minutes. This is for an engine that has been working.

I worked for a guy on dozers and his rule was. If you want to stand beside the machine and have a l;eak leave it running, if you want to get off and walk away idle it off for 5 minutes and shut it down or find yourself another job.

I have no problem shutting an engine down and restarting ias it is still hot with oil up in the engine.

Short and cold running are life shorteners of diesels.

AnswerID: 486410

Follow Up By: Hairs & Fysh - Tuesday, May 22, 2012 at 08:11

Tuesday, May 22, 2012 at 08:11
"Short and cold running are life shorteners of diesels. "
Agree RA.
And batteries don't like it either.
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Reply By: Axle - Monday, May 21, 2012 at 19:30

Monday, May 21, 2012 at 19:30
I reckon anyone thats started any engine by crank handle as a young bloke,

would be one of the guys to-day that would say ",Never turn the bastard off"

....LOL.


Cheers Axle.
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Follow Up By: Member - Dunworkin (WA) - Monday, May 21, 2012 at 22:40

Monday, May 21, 2012 at 22:40
LOL Axle, I'm with you on that one, many a time have I had to 'crank' an engine up by the crank handle and I'm not a bloke......... I was just a kid at the time and had to be very careful for 'kickback' not being as strong as grown ups...... LOL


Simba, our much missed baby.

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Follow Up By: Allan B (Member, SunCoast) - Monday, May 21, 2012 at 23:04

Monday, May 21, 2012 at 23:04
Ahh, Axle, you struck a chord there.
At Woomera in the 50's we had a number of Lister diesel generators at remote locations. No electric starters and absolute buggers to crank. You needed to crank up the flywheel revs as fast as you could then smack the decompression lever down to close the valves. If you didn't fire it at the first attempt you had little energy left for another try. So once it was running it was kept running until you left for home.

Cheers
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Follow Up By: Rockape - Monday, May 21, 2012 at 23:37

Monday, May 21, 2012 at 23:37
Axle,
if you read my post above one of the dozers was an old 14A D8 with the most awesome of all starters. Caterpillars bloody hand crank pilot motor.

Now that pilot motor came with a 6 volt starter motor that was made so it never worked and forced you to crank the bloody thing. I believe the starter and pilot motor were designed by some bloke called Marquis De Sade.

If you didn't get it started within the first couple of cranks you would spend half your day trying to start that machine.

Here have a go at cranking this C 27 Cat.

Image Could Not Be Found
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Follow Up By: Axle - Tuesday, May 22, 2012 at 08:05

Tuesday, May 22, 2012 at 08:05
Gotta be built like Arnie Rockape,!!...and some to turn that sucker over...Lol



Cheers Axle.
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Follow Up By: get outmore - Wednesday, May 23, 2012 at 23:01

Wednesday, May 23, 2012 at 23:01
Allan B (Member, SunCoast) posted

In the 50s you say?

I worked a job just a few years ago with lister gennies that started by crank,

seemed to start easily enough but I could see it getting old pretty fast.

one had an issue with air into the system so it would only run for about 20 min max

I think i finally fixed it by overtightening every fuel union

i couldnt find anywhere that had the seals for them to re do them
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Follow Up By: Allan B (Member, SunCoast) - Wednesday, May 23, 2012 at 23:26

Wednesday, May 23, 2012 at 23:26
Yes Get Outmore, the 50's......bloody long time ago now! And it was me "getting old pretty fast". lol

These things had a crank with the handle section being long enough for two people to hold it at the same time, but I never seemed to have the benefit of a second person to assist.

I did refer to the "decompression lever" when I should have said "valve lifter".
They did have decompression devices in the form of a large knob on the top of each cylinder which screwed a plunger up in the combustion chamber to vary the volume and hence compression for ease in starting. After the engine was running they were screwed down to raise compression.

Cheers
Allan

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Reply By: mikehzz - Tuesday, May 22, 2012 at 08:25

Tuesday, May 22, 2012 at 08:25
I drove a vw diesel around Europe. Every time I stopped at a set of lights the car turned the engine off. Touching the accelerator started it again instantly. So much for letting it spin down or whatever... It was a while before I got used to it I must admit. The first time it happened I thought I had broken down after 1 block. :-)
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Reply By: The Bantam - Tuesday, May 22, 2012 at 09:53

Tuesday, May 22, 2012 at 09:53
With the pewny little modern motors in our 4wds, i don't think it matters a jot.

If ya motor is 12 litres and the engine block weighs the best part of 2 tonnes, its probably a different story.
Back in the days of cheap diesel and Leyland flat sixes, the brisbane citty council buss drivers where instructed bot to turn their busses off till after their second run...it was considered it took that long to warm the engine up properly....may be?


With older heavy trucks, there where always reliability issues.

If you started a Mack with an air start without letting it run between starts (like moving the truck a few few feet to follow a loader), very soon you would find you where out of start air and looking for some air or a push start.

Because heavy trucks use air brakes, if you where on the brakes a lot before you turn the engine off, ( such as getting into a hole or ducking and shoving) you could find youself short of air when you start back up again.
Particularly when some trucks have a habit of leaking air when you do the wrong thing.

but these are all truck things and have no impact on small 4wds.

on the matter of turbo temperature.
On the OLD Mack I was driving untill recently the largest guage on the dash was the EGT ( exhaust gas temp) guage, you could be flogging the guts out of the old thing, and the EGT could be quite high, button off and the EGT would drop hundreds of degrees nearly immediately, I doubt that the bearing temp would be far behind considering they have their own oil supply.
The turbo components will be going thru drasic tempeature changes all the time the engine is running.

The single biggest thing you can do for your diesel is to change the oil regularly with a good quality diesel spec oil of the correct viscosity.

The other is to avoid short runs at low RPM and low throttle applications.

cheers
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Reply By: Ross M - Tuesday, May 22, 2012 at 22:23

Tuesday, May 22, 2012 at 22:23
G'day Cruiser 74

I hope you have a shovel to get through the pile.
AnswerID: 486509

Reply By: Ron N - Tuesday, May 22, 2012 at 23:39

Tuesday, May 22, 2012 at 23:39
Cruiser74 - Tony V has the correct answers. A diesel engine generates barely-adequate injection pressures at idle, and as a result, combustion is relatively incomplete at idle, because of low injection pressure and a poor injector spray pattern.

An idling diesel engine will generate a substantial amount of crankcase oil pollution from unburnt fuel. The inadequately-burnt diesel stays in the combustion chamber, loads up the cylinder wall, dilutes the oil film, and finds its way past the rings, into the crankcase.

A diesel with a few revs up (800 RPM or more) is generating full injection pressures and the injectors are developing a proper spray pattern and correct fuel atomisation.

In the U.S., in many cities, it is illegal - and you are hit with a large fine, for allowing heavy duty diesels (buses and trucks) to idle longer than 3 minutes. The reason being the high pollutant load from the exhaust at idle.

Cummins engines with PT injection are the worst for poor fuel burn at idle - but all diesels suffer from it, in varying degrees. Because the Cummins uses a unit injector (combined pump & injector), the engine needs more than idle RPM to inject fuel at high enough pressure, and atomise it properly. You never idle a Cummins with PT injection for more than 2 or 3 minutes if you can avoid it.

The only time you need to idle a diesel for several minutes, is directly after a long hard run, when the the valves, the exhaust manifold and the turbo (if fitted) are at a very high temperature (500°C or more). Idling for several minutes in this scenario allows the engine components to cool down, and allows the heat levels in the motor to stabilise.

I bet you're glad you asked, now!

Cheers - Ron.
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Follow Up By: Rockape - Wednesday, May 23, 2012 at 21:27

Wednesday, May 23, 2012 at 21:27
Ron,
yep idling does cause problems with old school engines.

That photo of the new C27 engine I posted as a joke for hand cranking but that engine was just ready to be fitted to a truck that had been ready for a mid life engine engine rebuild. The engine that came out had done 17000hrs in heavy dust but the big thing is they spend about half their life idling waiting for a bogger to load them. These are off course common rail engines and the operators need aircon all the time.

I still agree with you when you say don't leave the engine idling.
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Reply By: drowned_rat - Wednesday, May 23, 2012 at 20:53

Wednesday, May 23, 2012 at 20:53
You might also want to read your insurance policy, if you duck into the shop and come back out to find your pride and joy being driven up the road by an opportunistic thief, the insurance might not consider this theft and may not pay for the loss.
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Reply By: Ron N - Wednesday, May 23, 2012 at 22:21

Wednesday, May 23, 2012 at 22:21
I'm not sure about the other states, but under W.A. & QLD traffic regulations, leaving an unattended vehicle running - even if it's locked - is a chargeable offence. That has been law for over 80 yrs in W.A.
I found reports in the 1934 West Australian newspaper, of court records of motor vehicle owners being fined 10/- in that year, for leaving unattended motor vehicles running.
In this day and age, it only takes seconds for thieves to break a window or screwdriver a lock, to gain access to the vehicle, and that'll be the last you'll see of it.

Turbo timers are a grey area. If you have a turbo timer and remove the keys, apply the handbrake and lock the vehicle and move away from it (effectively "leaving the vehicle running" under the law) - then you probably have a lawful excuse to say that your turbo timer was effectively an approved shut-down method under law.

However, there are no vehicles built in the last 20 or 25 yrs that are able to have the key removed from the ignition and be left running.
So, effectively - if you're going to leave a vehicle idling (apart from a turbo timer), you're leaving it running with the keys in the ignition, and leaving yourself liable to a fine.
As stated, it's also highly unlikely your insurance company would pay out on a theft where a vehicle was left running attended.

Cheers - Ron.

AnswerID: 486609

Reply By: Member - Cruiser74 - Thursday, May 24, 2012 at 14:12

Thursday, May 24, 2012 at 14:12
Thanks very much to everyone for your thorough, detailed and hilarious responses! I guess I've got a pretty good idea now albeit a tiny bit confused. My 1HZ is not turbo'd at this stage so that side of things not really an issue for me.

A bit concerned about the lawfulness of leaving the car unattended while idling though. I am always out of the vehicle when the car is idling when I have the compressor hooked up and am putting air back in my tyres...often on the side of the road where I could be seen by Mr Plod. Always have the hand brake on and wheels chocked if I am on an incline or decline. I have never heard of anyone being booked for doing this. I suppose it depends on the definition of "unattended".

I think in the relation to my question I will be switching her off if I'm just ducking into the shops and after a hard run I always have her idling for a bit while I'm pumping the tyres up anyway so that solves that!

Cheers again folks.

Craig
AnswerID: 486648

Follow Up By: blown4by - Saturday, May 26, 2012 at 18:04

Saturday, May 26, 2012 at 18:04
Diesels work best under load. Idling glazes up the cylinder bores leading to premature oil burning. Starter motor overhauls are cheaper than engine overhauls. There is no advantage to leave it idling and plenty of disadvantages like oportunistic low lifes who take your car (and your missus if she is in the car)
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FollowupID: 762049

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