So I would like some opinions on idling. I've read here that these trucks shouldn't be run as 'grocery-getters', i.e. running short trips around town all the time. That's not a problem for me, I work all over several states.

But I'm wondering about idling in general. (I am a first time diesel owner, but have driven them for employers). I always heard that 'diesels work off the heat of the engine' - so I was instructed to always let them warm up before getting out on the road, obviously especially when starting in cold weather.

So is it better in general to let the truck idle when you need to pause somewhere on the job-site, or turn it off for a just a minute?

Thoughts? Sorry if this has already been hashed out previously...

 

It depends on how hard it's been working. It's always a good idea to allow the turbo to cool down after running hard but putting around town and rolling into a job site may be unnecessary.

As far as cold mornings go, not much need to let them warm up, empty, 15 seconds and take off, just don't push it hard until the engine reaches temp. If I was pulling 15k, I would let it warm up a little more just to the the oil thinned out a little.

 

Guzzle pretty much hit the nail on the head.I will add my .02

A lot of the thought of idling a diesel are left over from days gone by
If the engine has been worked hard it should be idled some to cool it off,so if you have a short stop may as well just leave it run

If done correctly there is very little difference between warming,cooling and idling a diesel or gas engine.The big difference is the mass you are heating or cooling and nobody ever gives the gas engine any thought

Once started and allowed to circulate oil and build some cylinder temp a light load is permissible and will bring the temps up fairly quick

After an engine is worked for a while it should be idled ( ideal is high idle) until temps are stabilized the can be shutdown.Generally this can be done driving down the street slowly

 

What they said ^^^^^^, thats what i do to a tee...

 

I was always told to let it idle at stops of less than 15 or 20 minutes because it took more fuel to start the truck than it did to idle that amount of time. True or not?

 

Well, On a cold morning...I personally would let it warm up at least 5 minutes, It puts alot of strain on your injector pump w/ the oil so thick and the injectors as well.

 

its not true. not on those trucks.i can see truck idling 20-30 min, using less fuel than truck thats off..... and if its really cold, its better to let it idle for 10-15 min , than shut it off and restart. less stress on the moving parts...
thats my opinion...

 

thats a myth about the more fuel when starting theory. dont worry about letting it idle.
now the tree huggers will tell you that you should turn off the truck at every stop, and maybe you should. but thats for emmisions, not engine protection.

as for cooling at high idle im not sure that will work as good as a low idle. but ether way is much better than turning off the truck hot.

the turbo keeps spinning after the truck is shut down and if its hot then the oil cooks to a point where it won't provide the floating that is needed for the shaft. it then touches the bore and Gaul's the bore/shaft. then the oil doesn't have the clearance any more that it has to have and things end up going bad.

one thing that some people forget is the coolant. if the truck is shut down hot then the coolant sits for lack of a better term, next to the hot spots in the head, the cylinder bores, next to the exhaust holes etc. as it sits there it boils, this is on a tiny scale, but as it boils it looses its ability to take the heat away from that area. then that area expands different from the other areas, or the heat frys gaskets etc. by idling the truck for long enough for the coolant to come down your achieving the best possible shut down.

im installing an accurate water temp gauge for just this reason. there are shut down control systems in the aftermarket to solve this issue. hopefully someone has one and can chime in.

 

if my Pyrometer reads 300 degrees or lower...I shut it off, I use to ;let mine idle down for 5ish minutes however I've been told by sources 300 degrees or less EGT's and the Turbo will be A-OK

 

interesting stuff folks, thanks