Diesel Idling

jbruels

Member
Aug 19, 2015
21
Question to folks with a big diesel pickup...

Is there a reason why folks like to leave their trucks idling? Now, I'm not talking about maneuvering a rig in to a spot or having to take more than one run in to hitch up a rig as you are leaving. I totally understand that. Some tight spots at campground can take me 20 mins or more to position right and level my camper.

I'm talking about folks who, for no apparent reason, just start up the engine and let that ol' "clatter clatter" and toxic exhaust toot away for no apparent reason. Just sitting there, 20 minutes or more, waiting for the spouse to come out and get going for the day. Sometimes even hop out of the cab and head to the john or re-fill the coffee and leave the vehicle sitting there, running...

Honestly! What's the deal here? One thing I remember about diesel is that engines have to warm up or run for a time before a truck pulls out but I thought modern diesel engines did away with that need. Another thing I heard about old diesel engines is that they consume a lot of fuel for ignition. It's "cheaper" to leave a truck idling than to have to turn it off and re-start it. Is that it? I really want to know!
 

jbruels

Member
Aug 19, 2015
21
This reminds me of the time my 460 truck was idling in front of my camper while I hitched up and a geezer walked by and told me "Pep Boys sells mufflers"....I reckon Cherry Bomb glass packs weren't his thing....lol
So, maybe that's just it? The rumble and clatter of the engine running is simply pleasing to these folk's ear? To each his own, I guess...
 
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generok

Super Active Member
Feb 7, 2013
3,472
Anchorage, AK
I used to have an F350 with the 7.3L diesel. I can tell you this much, I probably used a quart of fuel each time it started... more if it was cold. There is something about a diesel that lends itself to idling though, I can't put my finger on it. If it is cooler, and folks are trying to get defrost to work, it DOES take quite a bit longer to get a diesel engine's mass up to temp than a gasser. The problem is many diesel engines are simply louder than gassers. They do clatter, and more so when cold. So, I'm not sure if folks idle diesels more, or if it is just more noticeable when they do. I recall many a 4:30am departure for fishing that I would tap the starter and get it in drive and bug out from the CG as fast as I could, even though I really wanted to let it warm up for a minute or two. I don't know, it's just part of trailer life for me. I'm thinking of going back to the diesel next TV.
 

neighbormike

Super Active Member
Gold Supporting Member
Oct 6, 2012
4,166
WI
I love it!! The earlier and longer the better! And nothing accompanies a fresh percolating pot of coffee quite like the aroma of diesel….
 

Raycfe

Waterford Ct.
Oct 3, 2007
18,484
Waterford, Ct
At work we have drivers back into the warehouse and (try)to leave the diesels running inside. "You shut it off - we load you up"
 

Arruba

Super Active Member
Nov 28, 2014
896
Central Oregon
I have an old Ford with the 7.3 pre-Powerstroke Diesel. My Father has a 09 Dodge with the big Cummins. My last work truck, (I’m newly retired) was a 17 Dodge diesel. Here’s what I know:

1- Old habits die hard. People around my age and older who learned about them on the farm and on the job way back when left them running because as mentioned; it takes a bit of fuel to start them, they take longer to warm, running them under load cold is hard on them, and the turbochargers can be damaged if not allowed to warm and lubricate. Turning them off really hot is hard on them too. The old rule of thumb was to idle them 1 minute for every hour of full operation and add a couple of minutes to the total for anything after 5 minutes.

2- It takes a lot of battery to start them from cold. Repetitive cranking them from cold is hard on the batteries. On my old Ford, to re-battery it is a $350 to $400 dollar exercise.

3- The newer pickups won’t let you drive if it’s not warmed up enough and lubricated enough. My last work Dodge wouldn’t run beyond limp mode if not given a little idle time from cold. Granted it was weather dependent, summertime made little to no difference, wintertime it had to idle a bit to just take off first thing.

As mentioned, the newer Diesel pickups and medium duty trucks I’m familiar with shouldn’t be excessively idled as it starts plugging the exhaust filter, requiring more frequent regeneration cycles.

That’s what comes readily to mind.
 
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jmkay1

2004 Fleetwood/Coleman Utah
Oct 10, 2013
7,971
Northern Virginia
This is interesting. No one I know own diesel, didn’t realize there could actually be a reason people leave it to idle other than to feel special and annoy everyone. Like look at me I have a bigger, badder truck then you. Or like the Harley motorcyclist that love to rev the engine while sitting under an overpass just to hear the loud sound echo and crack like thunder. I figured the 18 wheelers are the exception though as their engines are built to give a ton of power regularly So probably more sensitive.
 

xxxapache

Super Active Member
Jul 30, 2008
4,572
I would guess a lot of quieter engines are started and left to idle, also.. You just don't pay attention. Many if not most newer vehicles have remote start that owners use to start to up the vehicle to warm or cool the interior to their liking.
 

ccarley

Active Member
Sep 23, 2014
231
Back in the early 2000's when I was an RV tech, I wondered about the loud diesels and firing them up in the morning while camping. And here I am, one of those guys now.

My 2000 Ford Powerstroke 7.3 is really annoying when cold. There's almost 4 gallons of 15W-40 oil in there, which is thick when cold making the truck slow. When it's really cold (not really, but cold anyway), it has this "added feature" of a warm up valve on the exhaust. It's basically an exhaust brake, causing back pressure in the heads to help them warm up and boy is that loud. If I try to drive in that situation, the truck really won't move. Living here in CA I cannot remove that warm up valve, it would fail the SMOG test if I did. If I'm hitched up and needing to pull out on a busy road, it's best to let it warm up so that the oil isn't so thick too, again that will cause the truck to be pretty slow. Another neat feature is that when it's below 40F, the computer automatically bumps the idle speed to prevent wet-stacking... the colder it is, the higher the idle (thus the louder it is). I've seen it around 1200RPM in 11F. The computer does what it can to take care of the engine.

What do I do? I generally will wait to fire it up until after 8:00am at the earliest. I make sure that I'm actually ready before firing up the truck as it can use a couple hundred amps in glow plugs and intake heaters, and of course to crank over the big high compression engine. Careful planning is key for not annoying anyone and preserving the liquid gold fuel here in CA right now (seems to be holding at $6.49/gallon at the cheap station). It's unfortunate that not everyone feels the same way and fails to plan accordingly (other half not ready or whatever).

Of course, we could also discuss car alarms going off in the campground...

Clay
 

ccarley

Active Member
Sep 23, 2014
231
I would guess a lot of quieter engines are started and left to idle, also.. You just don't pay attention. Many if not most newer vehicles have remote start that owners use to start to up the vehicle to warm or cool the interior to their liking.

Heck people here will park their car with it running and talk on their cell phone for an hour! **Camping or not.
 

xxxapache

Super Active Member
Jul 30, 2008
4,572
I admit to being an idler when not camping. If it's hot or cold, I often let one of my trucks idle when I am out of it to keep the interior the desired temp.
 

tenttrailer

Art & Joyce - Columbus, O
Jul 18, 2013
3,796
Thornville, OH
I don't get it?? I have a Cummings. I look in the Cummings owners manual they recommend not idling for more then a few minutes. They even have a fast idle selection on my cruse that takes it from about 700 rpms to about 1,000 rpm. What cumming says is at the lower idle there is to much fuel and carbon blow-by of the rings and you contaminate your oil. Requiring lower miles between oil changes.

Also, I read another article by Cummings. In which they stated at idle the engine never comes to temp and will cool too far down if it is at temp. Long idling and the cooler temps will cause the fuel not to burn well and result in a varnish build up on the heads, exhaust valves and top of pistons.
 

jbruels

Member
Aug 19, 2015
21
I don't get it?? I have a Cummings. I look in the Cummings owners manual they recommend not idling for more then a few minutes. They even have a fast idle selection on my cruse that takes it from about 700 rpms to about 1,000 rpm. What cumming says is at the lower idle there is to much fuel and carbon blow-by of the rings and you contaminate your oil. Requiring lower miles between oil changes.

Also, I read another article by Cummings. In which they stated at idle the engine never comes to temp and will cool too far down if it is at temp. Long idling and the cooler temps will cause the fuel not to burn well and result in a varnish build up on the heads, exhaust valves and top of pistons.

This is exactly what I'm talking about. Everything I've ever read about modern diesel is that extended warmup and excessive idle isn't necessary and probably damaging to the engine. It sounds like there may be some older trucks out there (90's and earlier) and a few ol' timers who have stubborn habits. Beyond that, it's simply carelessness or *ick swinging.
 




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