Warm-up procedures when starting from a cold start?

Well if they read the engine manual it says to not let the engines idle. If you must let them idle to bump them up.

 

I always thought it common sense if you bump the idle from 600 rpms to 1,000 you'll get better oiling not to mention faster warm ups.

 

Yeah I got a new engine. Cummins tells me too raise the engine up to allow the bearings to be lubricated before operating under a load. It also states to have a cool down of 3 to 5 minutes after pulling a load. This is from Cummins owners manual. Peterbilt set my idle at 850 to facilitate.

 

In the early 80s I ran heavy duty wreckers in the winter when layed off from construction in Southern Idaho. I remember towing a truck in that had lost oil pressure but was making oil bad. As it turns out, the driver had been stuck in Wyoming for three days waiting for the roads to open, and had just let his tuck sit and idle at low idle. The shop said that it had washed the cylinder walls and had raw fuel going past the rings into the oil, I assume because of poor combustion due to low operating temps.

Now this was a long time ago, it was not a new modern engine (BC Cummins), and he may have had other issues going on or a tired engine, but ever since that day I have idled an engine up to 1,000 rpms if I have to let it idle for any length of time at all. It seems to me that keeping cylinder temperatures up and fuel combusting better can't hurt, the extra fuel burned is nominal, and in the case of warming an engine it makes sense to me once oil pressure comes up.

I am anything but an expert on the subject so take it for what it's worth.

 

I don't think anybody is argueing the cool down after pulling a load. It's just that the cool down starts when you let off the throttle on the highway . By the time you get parked the 3 to 5 min is up. You don't have to sit there at idle for another 5 minutes.

Also 850 is not high enough.

What if you are empty?

The faster the warm up the better and driving it warms it up the fastest, just don't hammer on it.

 

The days of having to run your engine for quite a few minutes are long gone due to the invention of modern oils basically once your warning lights go off the dash board you are free to go, when you first start up though avoid revving the engine and leave it at less than < 1000 rpm till those lights go out then your good to go. The fact in a lot of cases it actually takes longer for you air to build up then for all the oil to circulate. With turbo engines it is best when they've been running for quite a few hours to let them cool down for at least 3 - 5 minutes so I would spend more time in the cool down procedure than in the warm up procedure so again leave the truck idling at below < 1000 rpm for a minimum of 3 minutes before switching off.

 

There is NO need to idle the engine for 3 minutes By the time you get parked the cool down is complete.
Modern oils will not coke up like the old oils. They coke at a much higher temperature if at all. Synthetics are better yet for that.

 

Caterpillar and the older Cummins (I.E. big Cam series) had a term that was used to void warranty. They called it a “Slow Turn” this only applied to when the truck was at idle. The bearings on the bottom side of the crank would get wiped out due to lack of lubrication. Bumping idle to anything above 750rpm would remedy this issue. Which was why drivers were taught to always idle up slightly till motor smoothes out. Obviously, this issue is not a big concern today. But it did happen often enough that manufacturers were wiggling their way out of warranty motor jobs. The 3406B, big cam 350/400’s were known for doing this when they were brand new.

 

Get up and start truck ...apu that heats engine .
Idle up to 800 rpm while I make bed and get coffee etc etc ...go to work .
End of day ...idle up to 800 rpm while I go in truckstop for whatever I need then shut off .
977k on turbo now without issues..2013 isx ....fingers crossed .

 

Per mack's recommendations, after oil pressure comes up bump it up to 1200 (I usually wait 2 min before bumping it up) and wait til water hits 140 and bounce out being easy on it.