20 min idle...did I do any damage?

[MojaveJoe]

Just read in my manual that I should not allow the motor to idle longer than 5 minutes. In the first 500 miles I probably idled the motor a couple times for 20 minutes in the driveway before or after normal driving.



I have read some threads about diesel going down into the oil pan, causing bearing wear, etc. Did this happen to me?



Is there a way to determine if fuel is in the oil?



Should I change the oil at 750 miles, or would that be a mistake?



Just a little confused now...



All advice appreciated.

 

[y-knot]

I do not think you have anything to worry about. It probably is best to keep the idle time to a minimum for the first thousand miles for break-in. But I wouldn't worry about your 20 min idle time. There is alot written about this subject, and I'm not to sure about all I have read. I am guilty of long idle times myself, some up to two , three hours. I don't believe I hurt anything, but I am not an expert.

 

[OTRPU]

Gettin colder lotsa places I land at night. . . I'ma looking for a better answer, but till then I found out it's lots warmer if I leave the trucka runnin and the heater on. Prolly doesn't do the engine much good. . . but whata fella gonna do? I know a hauler with a 95, has over 600k on that truck. He's run it 10 hours most days and idled it nuther 8 hours while he sleeps. Needs A/C in the summer and heat in the winter. Now that's a 1st gen engine, don't know bout the 2nd gens. . . guess I'll just haveta find out. Lots tougher on a truck runnin all day every day.



Cheers,

Steve J.

 

[DF5152]

the big problem with idling ur truck is heat or the lack of these engines need heat generated by crompressing air to burn fuel. when the engine is not working, like at at idle you dont generate alot of heat to burn the fuel and all the byproducts. so in colder weather you get deposits on valve stems piston and cylinder walls than can cause engine damage. unburned fuel can washdown the pistion wall and cause compression failures and oil dilution. idling 20 minutes will probably not due anything especially if the outside temp is warm and the engine is already warmed up. As far as cold weather goes try to drive ur engine warm keeping the rpms withing reason untillu develope some heat, at leat till the temp guage start to move off the bottom line. And in cold weather use somthing to keep exhaust temps up like an exhaust brake or restrict flow to the rad, which also has its drawback.

 

[jwilliams3]

You did not do any damage.

Just make sure if your going to idle for extended periods to drive for extended periods.



--Justin

 

[rbattelle]

I agree, no irreversible damage done. Just drive it hard a few times to burn out any deposits you might have left. And I agree with Justin about making sure you take it on long drives.

 

[Pugster]

We are in the fuel oil business making local deliveries. Our trucks often make 35+ deliveries daily. We often put less than 17 miles on a truck on any given day. These trucks spend the majority of their time idling. The only time they are turned off is to refuel, or while being loaded. We have been running diesels for over 30 years, both Cummins and Cats. If excessive idling would kill an engine, ours would have died years ago.

 

[Prairie Dog]

The newer ones are even less sensitive to idling. They burn cleaner and will automatically raise their idle if cyl temps get too low.

You did absolutely no damage.

 

[ttreibel]

I think all this idle talk is just that idle talk



Seriously you should go out and drive the truck, top off the tank, get in and empty the tank just to be sure the mighty Cummins is not getting a case of Asama.

 

[WadePatton]

I'll distill a few hundred of the "idle" posts for you. Or at least what I've concluded.



Different diesel engines respond differently to idling. The 12v's generate enough heat that extended idle shouldn't be an issue. The 24v's however will cool to the point of incomplete combustion, and those consequences. There is a reflash for this.



I've no idea how the Common Rail compensates for low temps, but I'm sure it does.



I think the EPA is anther reason "don't idle" is shoved at us.



No damage, DRIVE IT!

 

[EMD-Run8]

Read an article in trcking mag several years ago about generator packs for big rigs and the problems with idling for long periods. I remember the article saying that if you couldn't afford a gen-pack that you could minimize the bad effects of idlng if you could idle the engine up two or three hundred rpm's over dead idle. I guess this allows the engine to generate enough heat to offset the cooling effect of idling. Sounds reasonable to me.

 

[WadePatton]

Idle-speed devices are on the market. I use a stick jammed between the seat and pedal.