Extended Idle Time.....

Diesel D

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.....I recently viewed a video regarding letting your diesel engine idle for extended periods of time. The gentleman in the video stated that prolonged idle time puts excessive wear on the engine, and requires more frequent oil changes.....any thoughts??
 

gnathv

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Here’s some thoughts on it.​

IS IT OKAY TO IDLE A DIESEL?​

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You’ve likely heard that diesel engines are ok to idle indefinitely, and that it’s even good for them. Where does this logic come from, and is it true? Diesel Pickup Specialists, Inc in Inman, KS has the answers.
The truth of the matter is, yes and no. First, let's investigate where this knowledge originates.
Back in the day, diesel engines would be kept running for a variety of reasons; diesels can be difficult to start when cold, take a long time to warm up, and diesel fuel tended to gel if it got too cold, stopping up fuel lines and components. For these reasons, it was often better to leave an engine running than risk the hassle of shutting one off.
However, modern diesels operate a little differently, and much more efficiently. It is true that diesel engines use barely any fuel while idling, far less than a gasoline engine. Diesels are durable engines anyway, and a semi driver who lets his engine idle overnight to keep warm can still expect to get hundreds of thousands of miles out of his engine.
Even so, idling for extended periods of time isn’t good for your engine. While it isn’t particularly bad for it, there just isn’t much reason to do it; most diesels start perfectly fine when cold, warm up in a reasonable time, and don’t have gelling issues. Any time an engine is running, it’s wearing out, and idling isn’t great for efficient combustion or engine lubrication. The tradeoff towards keeping your engine running vs. turning it off simply doesn’t exist with a modern diesel truck.
Whether you drive a Chevy, Ford, or Ram diesel pickup, our technicians have you covered. For the best diesel service shop in Inman, KS, call or stop by Diesel Pickup Specialists, Inc, for all your repair and maintenance needs.
 

Clb

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The vid is from the prk....
ya'll that aint neer seen the pacific ocean, that's the gaybay bridge aka G.G.!-Lameanything west is useless as suckremento...
So mostly this...
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Fwiw
I did this with the 88 in the sig line for +- 30 min.
It rolled coal for the first mile...
Big rigs are a touch different.
 

Diesel D

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the info is great, but I'm wondering to what extent members of this forum let their diesels idle?....
 

Laine D

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My idi, if I really think about it, idles a lot. I do a lot of driving in town and commuting. Sitting at stop lights and waiting in traffic honestly makes up a lot of idle time. I go through drive throughs and stuff too, if there’s a long line I park and walk in.

I remember a lot of people saying that back in the 80’s the idi trucks (non turbo) were focused towards economy and people who towed a lot or needed a bunch of power probably bought a 460. I can only imagine the amount of folks who bought a 6.9 so they can drive a truck to work and then get potting soil on the weekends. So I’m sure a lot of trucks were idled around town before us as well LOL.

I’m sure it’s not amazing for it. I’m curious how detrimental it actually is.
 

sjwelds

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Here’s some thoughts on it.​

IS IT OKAY TO IDLE A DIESEL?​

You must be registered for see images attach

You’ve likely heard that diesel engines are ok to idle indefinitely, and that it’s even good for them. Where does this logic come from, and is it true? Diesel Pickup Specialists, Inc in Inman, KS has the answers.
The truth of the matter is, yes and no. First, let's investigate where this knowledge originates.
Back in the day, diesel engines would be kept running for a variety of reasons; diesels can be difficult to start when cold, take a long time to warm up, and diesel fuel tended to gel if it got too cold, stopping up fuel lines and components. For these reasons, it was often better to leave an engine running than risk the hassle of shutting one off.
However, modern diesels operate a little differently, and much more efficiently. It is true that diesel engines use barely any fuel while idling, far less than a gasoline engine. Diesels are durable engines anyway, and a semi driver who lets his engine idle overnight to keep warm can still expect to get hundreds of thousands of miles out of his engine.
Even so, idling for extended periods of time isn’t good for your engine. While it isn’t particularly bad for it, there just isn’t much reason to do it; most diesels start perfectly fine when cold, warm up in a reasonable time, and don’t have gelling issues. Any time an engine is running, it’s wearing out, and idling isn’t great for efficient combustion or engine lubrication. The tradeoff towards keeping your engine running vs. turning it off simply doesn’t exist with a modern diesel truck.
Whether you drive a Chevy, Ford, or Ram diesel pickup, our technicians have you covered. For the best diesel service shop in Inman, KS, call or stop by Diesel Pickup Specialists, Inc, for all your repair and maintenance needs.
These guys's shop is about 750 feet from where I work. The owner is a good friend of mine.
 

Kevin 007

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Yeah I agree that excessive idling isn't the best for engines, some tolerate it less then others. However due to my work and previous work that I have done; I do have things idling for long periods of time. (hours and sometime overnight in extreme cold) Whenever possible I will put a load on the engine and get the combustion temps good and warm after the extended idling. I take into consideration of fuel dilution of the oil and change the oil more frequently then I otherwise might. I have never had an engine, 7.3psd or otherwise that I have killed or excessively worn out with my practices. Sure, it's still probably not good for them but they have done fine with it.
And as for short idling times, Id much rather let a diesel engine idle for a couple mins instead of shutting it off, and re-starting it a couple mins later for no other reason then to avoid idle time.

And I also don't high idle to warm up my engines until the engine has had a chance to low idle for a couple mins to build some initial heat.
And I also let them idle a min or so to cool down before shutting them off, when applicable.
 

Farmer Rock

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I am old school, and was brought up being taught that the single hardest thing on a diesel is starting it up. I regularly high idle the engines for excessive periods of time, so they burn a little cleaner, and don't wet stack from all that unburnt fuel. If you idle a diesel for say an hour, on low idle, you will notice a nice big cloud of white smoke when you take off which is all the unburnt fuel being dumped into the cylinders, and they usually burn some oil as well. I usually idle machines for a couple hours, but I never shut them down without making sure to get them nice and hot under load to clear them out. I rarely shut equipment down during the day unless it's parked on a hill so it don't roll away. Obviously my pickup is an exception, because I don't like the idea of leaving any vehicle running unattended at most places. I have been known to drag someone along with me when I know I have to go to a few different local shops just so they can sit in the truck and I can let it idle,lol.
When I do shut them down, either way I always give them a couple minutes to cool down...........the engine that is...........Although the passenger is usually pretty steamed by then so.........
A lot of folks think that only applies to turbo diesels, but it doesn't. Even non turbo, you need to let the heads cool down a minute.
Also,Most over the road truck have a high idle mechanism/switch to bump up the throttle over night, or on board generators for places like Kali I suppose that forbid idling.


Rock
 

Powerstrokin350

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High idle is definitely better than low idle for longer periods. At low idle you do get more blowby because the combustion temps are usually a little low and won’t seal the rings as good. High idle will create more heat in combustion and seal them rings. At work, my truck doesn’t shutdown till the shift is over and I’ve idled it while getting my log book “caught up”. Idling a diesel at just about any RPM uses hardly any fuel, it’s the load that burns fuel.
 

Diesel D

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Thanks for the input. I'm not concerned about fuel consumption during idle. I'm concerned about things clogging up.
 
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