Question for Dodge Cummins truck owners

[Cityboyfarmer]

I know this might stir some folks up, but lets dicuss this politely, shall we?

I am a diesel fan with a 2003 Excursion running the 6.0. For a little background info, I worked as a tracked vehicle mechanic, tearing down and rebuilding 12 cylinder, 1,790 C.I.D. Teledyne Continental super-turbocharged tank engines from the crank shaft up, in the USMC for 4 years. So I have enough old diesel experience to be dangerous. /forums/images/graemlins/grin.gif

I have noticed a tendency of Dodge diesel owners to idle their trucks in public for extended periods of time. Being a diesel vehicle owner, I find myself noticing and admiring other diesel pick-ups as I travel about. I do not see the Powerstroke or Duramax owners idling their engines for extended periods of time. Is there a mechanical reason for this, or do you Cummins folks just think that loud Cummins just sounds cool?

On my way to Florida last Friday, I pull off I-75 and stop at a Flying "J" to fuel up. I idle up to the pump, take off my seatbelt and shut the engine off. As I begin fueling, up pulls a Dodge Cummins 2500 to my left, then a Dodge dually pulls in to the front. Both these guys idle the entire time they are fueling! The noise was deafening /forums/images/graemlins/crazy.gif

Next, we stop at a grocery store in Fort Meyers to stock up the condo for two weeks on Sanibel Island. Theres a guy waiting in his Dodge Diesel for his wife to come out of the store..yep, you guessed it, idling his engine the whole time.

First day on Sanibel Island, riding bicycles around the Island and what do I happen upon? You guessed it agian! Before I can even see it, I can hear the "clacka-lacka-clacka-lacka" of the Dodge owner idling in front of a local business.

I see this everyday, everywhere I go, and I just wanted to ask you Dodge Cummins guys: "Why all the idling??" /forums/images/graemlins/confused.gif

 

[LarryRB]

has nothing to do about being cool. It is called oil to the turbo bearings...

 

[gsxr1100]

The higher idle is wanted in any diesel to prevent diesel wash or washig the oil from the cylinders. Our company's powerstoke's run at 1,200 all day at security......

It is for either turbo cool down (lower EGT) or the higher idle when sitting there for hours.

 

[Cityboyfarmer]

Clarification:

1. None of the vehicles I observed were towing.

2. The Powerstroke manual recommends LOW idle cool-down when towing at max GVW and extended high speed (RPM) operation. I understand this.

3. The vehicles observed were operating at either highway or in-town speeds carrying passengers, but otherwise under no cargo load.

Under these conditions, why the extended idle time? How long does it take a turbo to cool under these conditions? Does the Cummins engine require longer cool down time at idle than other diesels?

The M-60 tanks were oil/air cooled and required cool down prior to shut down after pushing 50+ tons of steel around the desert. I am talking about a passenger truck that is water/oil/air cooled and operating unloaded.

 

[Hambone]

According to Caterpillar, Cummins and Detroit, reading out of the manual, if you are going to be stopped for more than five minutes, shut it off.
If operating at highway sppeds, must have low idle for three minutes prior to shutdown. I would consider idling up to pumps including this.
This is on truck engines and I doubt it would be any different for smaller engines.
Here is quote from the Caterpillar engine manual for C-10,C-12,3406E, C-15 and C-16 truck engines, manual number SEBU7186-04 Dating May 2001.
Page 83

"Avoid excess idling. If the vehicle is parked for more than five minutes, stop the engine. An engine can burn from .7 to 1.5 gallons of fuel per hour while engine is idling. Excessive idling can cause carbon build up and/or excessive idling can cause the engine to slober. This is harmful to engine.
If extended idle time is required, control the engine rpm to 1,000 rpm or above 1,000 rpm. Ensure that the coolant temperature exceeds 180 degrees."

That should answer that.

P.S. Yes, I am a diesel mechanic, but I did not stay at Holiday Inn Express.
Cityboyfarmer, I worked on the M-60's also, Turret Mechanic

 

[gsxr1100]

Sure I agree 100% (as I stated above). You idle for cool down to prevent cooking in turbo or you can idle forever if you are around 1,200 rpm (via idle controller). Normal idle will wash the cyl walls (too low rpm's)

So far, I have not stated anything new. All old news...years and years old.

 

[Dargo]

Let's see, is this the answer you are looking for: we leave them idling because it is easier to help jump start the PowerStrokes with the engine running? /forums/images/graemlins/grin.gif /forums/images/graemlins/tongue.gif

Actually, I pretty well shut mine off anytime I'm getting out of it. It is standard procedure to shut it off in drive through. As opposed to the 7.3 PowerStrokes, the Cummins engine is extremely easy to start. It would be the exception to have a 7.3 start in sub zero temps without having been plugged in overnight. I've never plugged in my Cummins; ever. Also, even in sub zero temps, I can't bump the key fast enough to not have it start. So, to me, if all it takes is a tiny bump on the key to start it, why leave it run? From highway speeds to the fuel pump, I'm idling at least 3 minutes while I'm pulling up to the pump. I see no use in letting it idle more.

 

[Bird]

Hmm, could be lots of reasons they don't kill the engine, I guess, and several good explanations have already been given, but the first two I thought of were:
1. Didn't want to turn off the air-conditioner - it gets hot in a vehicle in a hurry down south in the summer, and
2. Some may have been concerned about a weak battery that might not restart the truck easily. /forums/images/graemlins/wink.gif

 

[Cityboyfarmer]

</font><font color="blue" class="small">( Let's see, is this the answer you are looking for: we leave them idling because it is easier to help jump start the PowerStrokes with the engine running? /forums/images/graemlins/grin.gif /forums/images/graemlins/tongue.gif )</font>

/forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif

OK, Bird's observations makes sense, but let me add that I've been observing this idling issue for a couple of years now, and it doesn't get that cold in the winter down here and by far the Dodge Cummins owners are the undisputed world idling champions.

So what's the real reason, in addition to jump-starting us Powerstroke owners? /forums/images/graemlins/grin.gif

 

[gsxr1100]

I do see the same "action" about about local hangout.

The extending ideling is almost as cool as leaving the parking lights on also. /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif