Locomotive idling in cold weather?


K

kylewoody

Member
Hey guys,

A few weekends ago, I was hoping to catch the local working it's job, and was excited when I drove up and heard the engine running. Started talking to another railfan, and come to find out it's been sitting there for hours now idling, no one in it (their work done for the day).

He said they just keep them running when it gets cold (below freezing maybe?). So, I reckon it sat there idling that Saturday afternoon all the way until Monday.

Do they normally do this? How come? Is it really that hard to start the engine back up when it's cold? Seems very "un-green". :)

Thanks!
Kyle
 
Kyle, yes, they will leave the prime mover running if they are expecting cold weather down here. Where it's cold all the time, most railroads have installed block and fuel system heaters so the engine can be shut down. They also use a different blend of diesel fuel in the winter to help prevent gelling. Railroads use #2 diesel, which has a fair bit of paraffin. This causes gelling in temperatures below 20 degrees. So, shutting down the engine could lead to problems getting it restarted for an early morning job. It's not the "green" thing to do but we don't have to face really cold temperatures down here too often.
 
Huh, that's weird Jim! So how come they have to keep locomotives running, but not rigs, school buses, or even a Powerstroke Ford pick-up?

Is it basically the fuel is different then? As far as I know, no one has block heaters down here on them...

It just really baffeled me - I couldn't believe they'd let the engine run unattended for 36 hours, burning hundreds of gallons of fuel! Crazy stuff.

Kyle
 
One could argue, even, that it would be considerably greener to keep an engine from failing or getting damaged by an engine block freezing (they don't use anti-freeze) and having to repair the engine or replace it with all the energy that goes into an engine's production than it would be to keep it running at a low rumble for several hours.

Some diesels have auto-starts that run the engine up to temp and then shut it down to keep the block warm. This behaviour would be hard on starters and batteries, with the latter needing certain rpms in the alternator to charge the battery, and then over a certain time. More green issues if batteries and starters have to be replaced more often.

Also, diesels have tight tolerances and high compression ratios which allow them to compress about twice as much volume in one piston stroke as your typical gasoline engine. You can imagine that main bearings and piston rings get a lot of stress and wear when starting cold at the cranking process. So diesels are really best kept warm, lubed, and turning over, even if it burns fuel because it greatly reduces maintenance costs.

-Crandell
 
The AESS (Auto Engine Start-Stop) systems on both GE and EMD locomotives monitor out door temperature, cooling system temps, and so on. Every 5 minutes you'll hear a short ring on a GE locomotive indicating the AESS system is engaged. Then after about 30 minutes of idling in fair conditions the locomotive will issue a warning ring that lasts throughout the shutdown process, and the locomotive will be off. Then every 5 minutes you'll hear the bell ring while its off too. If the conditions are bad enough, the AESS system will keep the engine in Skip Fire Idle, or regular idle to regulate the engine temp. On railroads such as Alaska Railroad, the engines are equiped with Oil Pan heaters and such to prevent Diesel and oil gelling.
 
Here in southern CA on the BNSF, under 35 degrees we disable the auto start and leave engines running for battery reasons. Obviously in CA we are not too worried about freezing, but the colder temps require a lot more amps to start the diesels back up again. Therefore, our "rule" is under 35, leave them running.....cuz you need 1 long pair of jumper cables to jump 1 loco to another ;) Though are diesel service man does have that "long" pair of cables, he does not want to be called at 3am for a jump start! :)
 
I chewed out a lady once who left her diesel mulletwagon running while she filled it up!!! She said ".. but it doesn't have sparkplugs so it cannot create a fire...."

(sigh...)
 
kenw said:
I chewed out a lady once who left her diesel mulletwagon running while she filled it up!!! She said ".. but it doesn't have sparkplugs so it cannot create a fire
(sigh...)
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I think she had good reason to keep it running. she was saving the starter and keeping the car warm. in winter I will drive to chicago to LA and back the truck might turn off once the whole trip and thats in LA where its warm. LOL....

Diesels dont like to start when cold because all those bearing tolerances are very tight when the engine is stone cold. it puts stress on the starter,Batts,bearings, and any moving part inside of the engine. the oil is also very thick so lubracation to the top of the motor takes longer as the oil pump has to squeez the thick oil into the bearings. Cold start oil press can be 2 times the normal running press so stress on that pump is very high. then you have the water in the engine block without antifreez we know what happens with frozen water in a trapped space.
 
Old Rudolph diesel had no intentions for his engine to be started and stopped. It was intended that the efficiency of the engine was enough to leave it on at all times.
 
kylewoody said:
Huh, that's weird Jim! So how come they have to keep locomotives running, but not rigs, school buses, or even a Powerstroke Ford pick-up?
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As several old railroaders have told me 'It costs less to keep it running than it does to shut it down and restart it all the time', and having been a truck driver I know what a cantankerous beast a cold diesel engine can be.
 
In the late fall on the Camas Prairie in N. Idaho a UP GP38-2 would be hooked up to the rotary snow plow. Not MUed, all the power the GP made went to run the snowplow. Its wheel was powered by traction motors, the same as what was under the locomotive. It was disconnected in early spring. It would sit and idle for months and maybe make one or two trips to the prairie. Now the line is abandoned and half tore up and the snowplow is scrapped.
 
Steam lines freezing

In cold weather if passenger engines are not able to access yard steam they have to idle with steam generators running other wise the steam lines will freeze up. In Brewster where I worked they would add a second hostler just to watch over theses engines plus keep them supplied with boiler water.

NYC_George
 
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The GE's that were commonly used for local service in Kingman AZ were almost always running... It could be 110+ in the summer, and they would still be out there idling away...
 
Thanks for the all the input guys! Yeah, that just strikes as me as weird. I would have thought it would make sense to let it idle for maybe a few hours, but days or even months? :eek:

Learn something new everyday, thanks for the lessons. Now I guess it would be proto-typical to leave my SD60 idling on my layout when I go to grab a bite of supper. :)

Kyle
 
A couple more points to ponder, diesels fire on heat generated by compression, not sparks so cold = bad. Most railroads don't run antifreeze in the system so again cold is a no no.
Some AESS (Auto Engine Start-Stop) can be programmed to call the MOC (mech on call) and will play a recorded message: engine fail to start, engine # ____ or a variation thereof.
Most engine wear comes from starting and stopping, both gas and diesel.
 
lmackattack said:
I think she had good reason to keep it running. she was saving the starter and keeping the car warm. in winter I will drive to chicago to LA and back the truck might turn off once the whole trip and thats in LA where its warm. LOL....

Diesels dont like to start when cold because all those bearing tolerances are very tight when the engine is stone cold. it puts stress on the starter,Batts,bearings, and any moving part inside of the engine. the oil is also very thick so lubracation to the top of the motor takes longer as the oil pump has to squeez the thick oil into the bearings. Cold start oil press can be 2 times the normal running press so stress on that pump is very high. then you have the water in the engine block without antifreez we know what happens with frozen water in a trapped space.
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not really. it's a stinkin' pickup for pete's sake. it ain't even a real truck....

besides it was August in Houston.

and it is very, very illegal.
 
well I dont own a pick up so cant comment about those diesels but with a large diesel such as the one in my old Mack I will put less stress on the motor letting it run for the 5 mins while fueling than stoping it and starting it. with engine rebuild costs about the same as a new small car. I think I will rather just be labled as a crimminal.:cool:
 
kylewoody said:
Huh, that's weird Jim! So how come they have to keep locomotives running, but not rigs, school buses, or even a Powerstroke Ford pick-up?

Is it basically the fuel is different then? As far as I know, no one has block heaters down here on them...

It just really baffeled me - I couldn't believe they'd let the engine run unattended for 36 hours, burning hundreds of gallons of fuel! Crazy stuff.

Kyle
Click to expand...

We do have to keep them running. When its cold I dont shut mine off or I may not get it started. All diesels need heat and pressure in the cylinders to make combustion work properly. However I keep the truck plugged in at home when I will be there for a few days.
All Pickups and Trucks are built from the factory with block heaters. Thats what the little pugg hanging out under the grill is on most diseel pickups
 
Selector said:
One could argue, even, that it would be considerably greener to keep an engine from failing or getting damaged by an engine block freezing (they don't use anti-freeze) and having to repair the engine or replace it with all the energy that goes into an engine's production than it would be to keep it running at a low rumble for several hours.

Some diesels have auto-starts that run the engine up to temp and then shut it down to keep the block warm. This behaviour would be hard on starters and batteries, with the latter needing certain rpms in the alternator to charge the battery, and then over a certain time. More green issues if batteries and starters have to be replaced more often.

-Crandell
Click to expand...

Crandell is one of the only respondents to this thread to hit it on the head...

Most engines have a water cooling system and they don't use antifreeze. If the coolant water in the engine freezes, it will destroy the engine block (since when water freezes it crystallizes and expands).

So either it needs to be kept warm (by keeping it idling) or the engine block needs to be completely drained of water, which you can't do if you expect to use it again soon because you'd have to refill it again.
 
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