Extended low idle will allow cyl temp to drop low enough that complete combustion wont happen and may allow some cyl wash down. You need to high idle if sitting still for more then 5 min.

 

Thanks for info...

 

i think the old navistar t444e used to have a sticker on the dash telling you to idle it at 1250 rpm in cold weather to avoid engine damage. thats kinda screaming, but im sure they told you that for a reason. funny thing is i dont think the 7.3 psd (more or less same engine) had the automatic high idle like the 6l psd or vt365 does.

anyway tell them to go indoors and close their windows if they dont like noise. i live in an apartment building and work night shift. i sleep through everybodys noise. i dont shut tow truck off untill call is done, that murphy is a real dick and would prob make sure my starter was on a dead spot if i shut the truck off with a car on the deck.

people complain because it makes them feel more important. i remember a story about an airport that was closed for several days to air traffic while they did some repairs to the airport. they still got noise complaints about aircraft even though there were none!

 

I don't like to let my diesel truck idle more than a minute, cause I have a DPF & it'll clogged it & then it will regen. wasting diesel fuel

 

Running a diesel at idle for long periods of times causes more harm than starting and shutting off. Buy since your fire, you proably need to leave them running for the electromincs, water pumps and your Lights.... Or you will be jump starting a cab over fire truck...

 

most fire trucks and ambulances that i have worked on will kill the batteries and not restart if you shut them off for over an hour, the power inverters, cooling fans, strobe lights and safety equipment all drain the batteries, so obviously the truck needs to run to re-charge them.

 

as far as my trucks go, We can not shut them down anywhere but back in the bays with the shore lines pluged in. If we need to move a patient fast or leave 1 call in a hurry for another, we dont have time to wait for the engine to start back up and refill any lost air. Our scene lights are run off a genny, but the truck battery is wired directly to it for electric start. Even our brush trucks remain running during any exercise just to make sure the bateries stay charged. If one of our brush trucks get shut off, It is a very good bet that it will have to be jump started to get it running again. Just my .02

 

a buddy of mine worked as a aircraft refueler for a while and they left the tankers all running 24/7 in the winter. ol scabby gmc medium dutys with 8.2l detroits. i always get a laugh when you see a classified ad for an airport vehicle and it says "low miles" prob has 9,000,000 hours on it though. i bet even the miles are pretty hard i guess they beat the **** out of those things when he worked there. he told me he was behind one that took a corner to hard and it had both duals on the inside of the turn off the ground. fuel must have sloshed a bit

 

well i work for the railroad, and our diesels make even the baddest semi truck engine look like a toy. And in the winter months most if not all the engines on the locomotives are left running throughout the season. This is done for many reasons number one being there is just plain water with rust inhibitors no antifreeze in any locomotive engine, because certain locomotive makers namely EMD aka general motors do not allow it because it is harmful to the bearings in the waterpumps etc. Secondly a typical diesel of this size may hold up to 400 gallons of coolant and having to purchase 200 gals of antifreeze is too expensive. Also the compression is lower than your regular truck diesel (about 14:1 ) they can't tolerate cold as much. Thirdly the starting process can take up to ten minutes and a few more to warm the engine up to make it ready to put the load on it. Its just not sensible to shut it down when its gonna be used a hour or so later in the yard or where ever.

Although nowadays with everyone getting more and more concerned about the environment several companies have developed ways to shut locomotives down to save fuel and emissions etc. Most if not all newer and some olders ones have been fitted with an auto start feature which starts and shuts the main engine off to maintain water temp and battery levels, it is however disabled at outside temps lower than 40 deg f. And on the newer and rebuilt locos it can also kick up the rpm on the engine if the turbo, the traction motors are hot, or the air brake pressure is low, or water temps are not high enough etc. sort of like high idle on a truck.

Another thing now there are APU's like on a rig only slightly larger, Buffalo and Pittsburgh railroad has a few prototypes of these utlizing a cat C7 engine. the small engine stays running when the loco is inactive for long periods of time and keeps the larger engine warm. Another new thing is gen set locomotives using a few smaller engines instead of one large one. The few ive seen use Cummins KTA type engines and are able to be shut off when not used.

And about people complaining, you bet your bottom dollar they do, we always hear complaints about the noise and the so called bad smell. I say we work hard every day sacrificing time away from our families, and its not like the job is not without its dangers, we strive every day to provide you with the products you love so much and you're gonna complain

At least the EMD F40PH screamers passenger engines have been all but have been all but modified. Passenger locomotives and cars used to utilize steam heat and seperate generators for lighting. old locomotives had a diesel fired steam boiler on them. In the 70's heat, lighting and A/C are all run electrically. First designs to utilize HEP (head end power or hotel power as its called) used an alternator driven by the main engine. Problem was the in order to produce the 60hz power the engine had to turn at 900 rpm. which is full throttle for them. The power to the loco wheels was controlled by varying the field on the drive motors in the axles. They were quite loud when they were parked at terminals at the end of their runs at night, screaming at full throttle they could be heard for quite a while people did complain left and right Commuter lines still use these locos but they have been outfitted with and aux engine to drive the alternator most use a cat 3406 or a cummins n14. They are much quieter as the aux engines use a muffler and most older locomotives have no mufflers what so ever. Amtrak's diesels still use the older method of driving the passenger power alternator off the main engine but the newer GE FDL 4 stroke diesel with a exhaust silencer is much quieter than an older EMD Two stroke diesel.

 

Just tell them its their hard earned tax money at work. Smile and say thank you. I leave mine idleing on cold days all day if need be. Like said before little fuel is cheaper then batteries and starters