Community Forums

danlhsb · 11-15-2013, 09:55 AM

I have noticed at fueling stations and rest areas that the truck drivers usually do not turn off their diesel motors while they are stopped. Does anyone know why this is? Should we be doing the same thing with our Class A diesel pushers? Just curious!

Thanks!

Dan Leffel
Newmar Ventana LE 35'

RickO · 11-15-2013, 09:59 AM

I can't speak for the truckers, but I don't think there is any reason to do this with our DPs.

I make sure that before I shut her down, that she has had time to cool the turbo, but that happens in the few minutes it takes me to get from the freeway to the pumps.

Rick

HD4Mark · 11-15-2013, 10:10 AM

I think it is possible that they don't use enough fuel to warrant shutting them down and actually use more to restart. Plus that is the truckers home and office so whatever they are running in the cab may need the 12V, a/c or heat to be on.

That said we shut our DP off while fueling but often leave the generator on to run the house a/c. Diesel is much less likely to ignite from spark as gasoline so there is less danger.

cucamelsmd15 · 11-15-2013, 10:22 AM

I can field this one.

First reason is that yes, they require very little fuel to sit and idle. On the order of 0.75-1 gallon per hour for most newer trucks. Second reason is to keep from having to re-pump air system, which saves wear/tear on those parts. Not an issue for a DP that sees only a few thousand miles of use per year. Third reason is that the truck is generally powering everything in the cab. I stopped in Dayton, OH last year on a trip with the toterhome and put 175 gallons of diesel in it. Left it running the entire time so I had 12v power inside while I waited. Fourth reason is to keep the motor warm, especially when its cold outside. Big diesels dont like being shut down and restarted as a general rule, but having a cold big diesel? Yeah, good luck with that.

Disclaimer: experience is with a Freightliner with MBE 4000 12.8L engine.

road dogs · 11-15-2013, 10:32 AM

Another theoretical reason is that some folks believe every time you start a diesel motor, it puts stress on the starter motor and those are not cheap/easy to replace. Some states, like Cali, have anti-idling legislation that gets enforced by the local Prius huggers.

BFlinn181 · 11-15-2013, 11:57 AM

Another reason for fleet trucks is the driver isn't paying for the fuel. After a short cool down, as Rick said, drive from exit to park, I shut it down. I am paying for the fuel.

Route 66 · 11-15-2013, 12:33 PM

Quote:

Originally Posted by BFlinn181

Another reason for fleet trucks is the driver isn't paying for the fuel. After a short cool down, as Rick said, drive from exit to park, I shut it down. I am paying for the fuel.

gnrenfeld · 11-15-2013, 12:55 PM

Another reason for fleet trucks is the driver isn't paying for the fuel. After a short cool down, as Rick said, drive from exit to park, I shut it down. I am paying for the fuel.
Of course sometimes to run equipment with in the cab. Many units now have Aux generator's with heaters so they can shut down and save the Company wear and tear on the engines because they don't like cool operation. Now my years before RVing I did idle as well many times for 6-8 hours. I guess there are so many points of view on this issue that we can not relate to the trucking industries trying to get 600,000 miles before wear and tear problems.

devans47 · 11-15-2013, 01:19 PM

In the old days many trucks were very hard to start when they were hot. I think this may be a hold over from those days when thery were afraid to shut them off because they wouldn't start again. I drove an old GMC truck in the oil fields and had to be pulled many times to get it started.

dsbike · 11-15-2013, 01:25 PM

One thing to remember, if you use DEF then your system needs to be idling above 1000rpm which technically is not idling. The system needs to be above 600'F to turn the soot into ash. Per Cummins , no more than 15 minutes at idle and normal operation is 3-5 mins idling, then high idle (anything above 1000rpm).

You can idle as long as you want , but your engine will start putting up codes, it will rejuvinate the soot itself in the first 3 warning conditions, but each condition takes longer than the previous to perform it duty, this can be as much as 8 hours at highway speeds. You can also perform this manually by unplugging a conector & plugging it back in. The time is much quicker this way. I have never had to do this, yet!

Selah · 11-15-2013, 07:35 PM

Dsbike... Bingo
At least that's what my Cummins manual says.

SuperGewl · 11-15-2013, 08:46 PM

As a former diesel owner, you only need to get the turbo exhaust temp down so that you don't cook the oil in the turbo. If you exit the highway and have a long exit ramp, by the time you get to the fuel pump your exhaust temp should be down enough to not really have to let it run. I had an exhaust temp probe and shutdown timer which would run the engine for a max of 3 minutes and or when the exhaust temp reached 400 degrees, whichever came first.
More than that is not necessary according to Cummins.
As others have stated, OTR truckers leave theirs running because of being OLD school and or because they are running other things that require power.
You have a generator that is designed to run 24/7 and power everything in the MH.
So shut it down ASAP unless you enjoy paying for the fuel and possibly the ticket.

Tom N · 11-16-2013, 06:33 AM

"The engines of many big rigs are still running in parking lots, four years after Pennsylvania made it illegal to idle longer than five minutes an hour."

"At present the law is on the books, but is not having a big impact on behavior," said John Henson, a biology professor at Dickinson College, Carlisle.

"Pennsylvania is among 37 states that has a state or local anti-idling law on the books."

On idle: Law rarely enforced against idling big rigs - Chambersburg Public Opinion

palehorse89 · 11-16-2013, 06:47 AM

When you get caught speeding you will get a ticket and you are fined, so as far as the "idling laws" , who is to blame for not enforcing them? A the big question........why aren't they enforcing them?
OK , Now everyone reads the the sign's that are everywhere about this law but no one is getting arrested for breaking this law so............let them idle! Police officers or maybe the D.O.T officers, is not doing thier job that they are getting paid to do! Maybe speeding tickets generate more revenue?