did not want to bump the other thread so ill start a new one. why is too much idling bad for the truck, or what is considered too much idling. i leave my truck running all the time...Its a diesel, If i have to sleep in it ill leave it running all night. I didnt know you could idle i diesel too much. I understand the carbon buildup in the exhaust but you can blow alot of that out cant you?

 

i idle my trucks all the time never had any problems with them at all

 

i think it is something to do with the 24V heads flowing too much air keeping the combustion temps low enough to where all the fuel doesnt get burned causing varnish to form on injectors and the cylinder walls. If you have a auto the dealer can enable the manual high idle which you can set anywhere from 1100-1500 rpms. dealer did mine for free and it works great.

 

Nice feature to have but only for those of you with an 04.5 or newer. People like me have to depend on our installed exhaust brake.

 

Supposedly it creates a situation called "cylinder wash down", due to the fuel not burning completely in the combustion chamber.

I don't have a need to idle excessively, so therefore I don't. But I have yet to hear of a documented case here on DTR or anywhere else where idling caused a problem on our engines. You would think if there was a problem it would have been mentioned here somewhere at some point.

Personally I believe there is only the smallest fraction of extra wear on the engine over the course of it's lifetime from idling. In other words, a Million Mile engine may only go 975,000 miles instead.

I have asked this question before in several other threads on this topic and have yet to have a negative response.....

Does anybody know of a documented case where a Cummins engine failed, blew up, burned up, burned oil, showed excessive or premature wear, or have any other problem due to excessive idling? If you do, please speak up! Otherwise, I believe it is a myth.

Idle on! (if you need or want to)

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The combustion temp at low idle is a dilemma on any diesel I've known.Not just 24 valves.The 'burn' is not efficient,temp to low.The 89 First Gens came with a pull throttle to up rpm as needed.The engine is not a million mile motor.Its a good one granted, but its not rated a million miles.I've read of several used high mileage(300 plus)being torn down and lots of wear.In fact ,worn out.Lots of valve stem and guide wear,worn cylinders,copper showing in bearings and yet ran OK etc.

 

mines being torn out of my truck. i have a 2004.5 with 215,000 km and melted piston, bent rod and messed up head. wow

 

nickel says that wasnt caused by a lot of idle time

 

"Cold" idling is bad. Any amount of extended idling is really just a waste of fuel. Define "extended?" But cold start idling at anything less than about 1200 rpm's is definitely hard on the cylinder walls.

 

so start truck and immediately raise idle up to 1500 rpm? i dont think so. i usually start mine cold in -40 celcius and then let it idle for about a minute and then i manually bump rpms up to 1100

 

Well i dont go to a baseball game and leave my truck running outside, but like when i run into the convienient store i leave it running, and when i fill it up with fuel, or if i park and im sitting in it. Things like that i leave it running.

I cant imagine it being to good for your motor to start it up cold and immediately have it reved up. When mine is cold it will run for about 30 seconds or more and then it will rev itself up and idle high for a while.

I want to get that manual high idle but i dont know any dealers that will do something for free.

 

As a former truck driver I asked the service department. Their response was the same as an internationally known diesel engine expert: cylinder wash is real, blowby is increased, and some nasty junk start to accumulate in the oil. The last is the one that matters. Extended idle (as a function of mph versus time) is hard on oil. Period.

Now, do I worry about it on a day of 102F and my wife is running into and out of the store; maybe 8-10 minutes? No, but as I keep a log of my OCI complete with engine hours vs. mph, I can keep track of it.

As to how long these engines last: a few years back Cummins said 350,000 mile TBO. GM & Ford were 250,000. This is probably in commercial service where records are kept.

 

Well, we have yet another thread with the "wet stacking" debate enduring.

I know Cummins says to not idle them. I know mechanics tell us we shouldn't idle. But I still have never seen anyone come on DTR and post about their own experience with a problem with THEIR cummins engine because they excessively idled it. (Sallyman's problem im sure is not due to excessive idling....)

I hear stories of guys idling their trucks all day (start up and don't shut off all day while they run errands, talk etc.).......some others are run constantly for several months of the year. Please, if anybody has a thread or some first hand knowledge about a problem from excessive idling........speak up. I "Triple Dog Dare" ya...! Otherwise I say Myth!

I am not trying to be argumentative. I just want to hear about it so I can either agree or not. So far the Nays have it, imo.

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Well, I think this is on the same lines here. I worked in Prudhoe Bay Alaska for 4 years for Halliburton and during the winter, our 7.3 and 6.0 powerstrokes never shut off. The only time was when they were recieving an oil change. Temps in the winter time averaged around 45 below. Rangeing from 20 to 80 below. It seemed they could only go about 65 to 100,000 miles before an overhaul or before they were toast. Now yes, I realize they were Fords, but if they idled that long, how many miles would that have been equivilent to? So, was it the time on the motors, or was it from the ideling? Don't know. Tell me.

 

Low combustion heat with a high flash point fliud like diesel just sounds like trouble as in high wear etc.Oily fliud like diesel needs a lot of heat to burn efficiently,that's a given.At low rpm that doesn't happen.I have no proof of the wear it may cause but it sure sounds like it could.I think I'll believe the engineer's and mechanics that handle these issues for a career.Low combustion isn't good for a furnace or chimney.Makes sense to me it wouldn't be good for piston's or rings in a motor.If that wasn't the case would not need grid heaters or glo plugs to fire them and help the burn.Doesn't sound like rocket science to see the issue with low speed combustion temps.