Idle and Diesel Wear

[hammersley]

Found this statement from the following:



http://www.epa.gov/region1/eco/diesel/assets/pdfs/Diesel_Factsheet_Truck_Idling.pdf



I Know it's EPA - BUT forget that part - is there any truth to what they are saying????????





Engine Wear and Tear



Letting an engine idle actually does more damage to the engine than starting and stopping. Running an engine at low speed (idling) causes twice the wear on internal parts compared to driving at regular speeds, which can increase maintenance costs and shorten the life of the engine. Generally, fuel consumption during engine start-up is equivalent to about 30 seconds of engine idling.

 

[y-knot]

This probably isn't the PC answer, but I never worried about it. There has been many,many times I let the truck idle for several hours. Others might not want to do as i have and still do, but I am not worried about the subject. On most jobs, the work trucks never get shut off till it is time to go home. They sit a idle all day long, and are very often the only source of heat and shelter to the cold and or wet weather. I think if it bothers you then just shut the thing off and drop the subject, but let it be known that everyday there are hundreds and thousands of diesel idling away around the US. I have never worked for a contractor that had Dodge for there fleet vehicles, It has always been Fords. Maybe the Fords are tougher or built better then the Cummins?? Think so?? They never seem to find, setting there all day, idling along. They use very little fuel, just a couple gallons for the whole day, and still seem to live.

 

[QRTRHRS]

Years ago, I worked in excavating. During that time, things were different and most work stopped during the winter. We got called out to replace a frozen water line for a ski resort. Being so cold, our old D6 (military surplus) was a bear to start so we let it idle. The cylinder walls must have glazed over because after that it was pushing oil out of the stack. The oil can get so thick in a big diesel that it won't even turn over. I saw someone destroy a clutch pulling a truck with a stiff engine trying to turn it over.



Early seventies, the contractor I was with leased his tandems on with the state for winter road work. They had those throw away cat V8's. The state would call us out often to only standby idleing. I saw some glazing problems but mostly, the water temp would drop so much you had no heat. We carried a stick to keep it throttled up.



With the temps dipping to the singles lately in my area, we let the trucks idle all night at work. I set the cruise to idle it up a bit.

These are all retired line haul tractors with 400-700k and no teardown for the most part.



I used to use a farrier for my horses that had a 96 Ram. At that time he had 115k and idled all the time. I guess it's a matter of priorities.



Personnally, I don't let my Ram idle overall. If it's real cold and I have not plugged in, I may idle with the exhaust brake on for 5-10 minutes.

 

[Hale on wheels]

Since I have an auto and no exhaust brake, I chock my wheels, apply the emergency brake, and put the truck in gear to let it warm up a bit in the mornings when it is cold (keep in mind cold here is ~35F). That keeps enough load on the engine that I would think that it is not a problem. I hope I'm right!

 

[Cooker]

Increased wear on an engine due to extended idiling it a reality. The decreased combustion temps and washdown of the cyliner walls are the results of extended idiling. There was a TSB out about extended idling on a 24v causing the values to varnish up due to the decrease in combustion temps.



If you need to idle for extended periods of time a high idle device or an exhaust brake will help keep combustion temps up.

 

[bulabula]

I understand the concern about wet-stacking and fuel dilution...



But, you have to keep in mind the reason for the EPA's being: minimizing pollution; and not really interested in the material status of your engine.



Bottom line: the EPA is saying that if you shut down the engine, it isn't polluting.



Here's a corollary... .

If the EPA can withstand the lobbying efforts of the oil industry and quick oil-change industry, maybe they can try and minimize the so-called paranoia about having to change oil every 3000 miles. And with all the great strides made in our modern lube oil, even the major Auto OEM's are recommending increased oil drain intervals these days.



But if we decreased the amount of waste oil generated, we'd cut into the oil industry revenue, and probably contribute to the loss of jobs in the quick oil-change industry. And nobody in the govt wants to be accused of eliminating jobs.

 

[JohnE]

I really doubt the control parameters used in some of the government studies, especially states as Taxachusettes.



Low speed idle IS very hard on diesel engines and is a very recognised problem. That's why engine manufacturer's require high idle devices since the 60's!

In the winter we reset to 12-1300 rpm to prevent the very problems mentioned as glazing or washdown, valve deposits, cool block temps, wet stacking (water condensing in exhaust). It will even get more stringent with emission control devices (EPA shot themselves in the foot on his one). CAT ACERT engines must be VERY warm to function.



Problems exist that we don't have always have a source of electricity for plugging in the heaters; we don't have unlimited battery reserves for running the aux heaters (Espar, Webasto, ProHeat, etc. ); or a regulated supply of winterized fuel (3 suppliers in town all had gell complaints from their winterized fuels in the recent cold snap).



COLD starting a diesel is very very hard on them. You cause more fuel washdown starting a cold engine than anytime in the life cycle. The comment on "fuel consumption during engine start-up is equivalent to about 30 seconds of engine idling" only applies to a warm engine.



When you idle, either run very fast or load the engine.

Personally, I use a stick and get it around 1,200 rpm. Engine stays warm and so does the cab.



Me? I must know nothing compared to the EPA. Just an Ex-JD mechanic & Propulsion Engineer.