I had once saw a railroad work crew working on the tracks out West, and there was an engine nearby that?

Question

was just idleing. It seemed to have just sat and idled all day. Seems like that would be harmful to the engine. The diesel engine was turning so slowly, I wonder how all of the parts were kept lubricated? Do you know anything about letting huge diesel engines just idle for long periods of time?

Answer 1

those big [and i mean big] engines can go soooo slow....when i lived near the tracks by the long island RR ...they idled 24/7....they used almost no fuel and were h**l to start so they left them running...my best bud worked as a mechanic...

Answer 2

It does no harm to them at all.

Answer 3

It's not harmful to them. They can sit and idle for months. And they can go for years without being shut off. A diesel engine  really doesn't generate that much heat, unless it's working hard. The internal parts are lubricated by an oil pump, just like any combustion engine. Here's some trivia for ya. At one time, there was a difference between an engine and a motor. An engine had pistons and a motor didn't. i.e. motor was electric - rocket motor, etc. But now we interchange the two words to mean the same thing.

Answer 4

you dont shut them down, they run for weeks ata time, And its a good question, because my father was the head supervisor for conrail for matience man, and work crew on the railroad, Yes the lubrication lasts for weeks on end,

Answer 5

yes it;s comon to see a locomotive run for those small amount times now that most transportatation companies have a shutdown policy and thats for the locomotive is turned off and not leftrunning  for a specific amount of time it also saves fuel useage a locomotive can use 300,000 gallons a year or more

Answer 6

They are designed to idle indefinitly, the only problem is it might smoke a bit when I starts to work due to excess fuel build up in the cylinders. They have a large capacity oil pump to keep everyting lubricated. Recently most railroads require locos to be shut down if they are going to be sitting very long due to fuel costs but it is actually better for the engine to be left idling, deisel fuel is a very good lubricant, much better than gas so even the upper cylinjder parts are not being harmed.  

I dont recollect the numbers but a loco left idling will use several gallons an hour, so if every engine not in use is shut down, the RR can save several thousand dollars a month.

Answer 7

I DID NOT REALIZE SO MANY FOLKS WERE AWARE OF THE USE OF DIESEL ENGINES -- UNLIKE A GAS ENGINE IT IS BETTER TO LET IDLE AND ALSO LIKE ONE OF TE FOLKS POINTED OUT IF YOU WORK A DIESEL ENGINE VERY HARD YOU HAVE TO LET IT IDLE FOR A PERIOD OF TIME BEFORE SHUTTING IT DOWN SO IT CAN COOL OFF.  A LOT OF GOOD INFO THERE.  GLAD YOU ASK THE QUESTION -- BY THE WAY THESE POINTS APPLY TO THE FARM TRACTORS WE USE EVERYDAY.

Answer 8

Indeed, as others have already well stated, diesel locomotives can run for an near-infinite amount of time and most of the Class I power used daily or almost daily remains running until regular maintenance takes it out of service.

Leaving them running doesn't hurt the internal components at all (remember, almost all locomotives you see in service are built for this type of heavy usage, and many log millions of miles before they're retired) and it is especially useful during winter months (it's very difficult to restart them if shutdown in the bitter cold).

Answer 9

One more point that the others forgot to mention is the temperature.  An engine is left running if it is going to drop to 40 degrees or below.  The water in the cooling system does not contain antifreeze, so you don't kill the engine when you are through working.

Answer 10

Keep 'em lubricated.

Large diesel engines often don't turn more than several hundred RPM anyway, so the oil system is designed for that. It could be they needed the electric generator, so that's why it was left idling. On a large engine like that, because of the size of the parts and the stresses involved, it's often the number of heat-up / cool-down cycles that limit life on the engine rather than just running hours. Also, if the oil pump is mechanical and only turns with the engine, then every start causes wear on the engine since the oil isn't really pumping until the first couple of revolutions, so every start is a bad one.....

Answer 11

Diesel engines can be left idling for months with no ill effects on them, other than normal wear and tear.  On the rail road they are left on because actually they are hybrid engines, diesel motor turns a generator and the engine moves under electric power.  With the engine on they have cooling, cooking, etc. ability to meet the needs of the crew.

Answer 12

All good info.  No doubt.

Prime movers, in the 'good old days', when diesel fuel was cheap, were left running for two main reasons:

Constant starting and shutting down obviously subjected the diesel to swings in temperature.  This, accompanied by the expansion and contraction that the temperature swings create, had the potential to create metal fatigue, and, ultimately, failure of internal parts.  Fuel consumption is quite low when idling, but, that small number looms large when taking into account a huge power roster, such as most railroads maintain.  

The associated fuel costs of operating locomotives ran well over $1,000,000 a day with a large fleet, back in the '80s. But, fuel conservation began before that, after the embargo by oil interests abroad in 1973.

It is around that time, early 80's, that carriers began fuel conservation in earnest, including shut down of engines.  At todays fuel prices, that number is significantly larger.  So, the savings generated by shutting the engines down is greater than the costs for frequent prime mover re-builds.  So, most railroads have adopted the practice of shutting engines down for fuel consumption, under most conditions. If predicted overnight lows were 40 degrees or less, engines were to be left running.

As pointed out above, the cooling water systems found on board do not run anti-freeze.  The water looks like it has anti-freeze in it, but this is actually a dye that reacts to ultra-violet light.  When performing regularly scheduled running maintenance, a black light is used to detect small leakage from the system.

Dead batteries are also a frequent problem when trying to re-start, but this too is a small price to pay when compared to using more fuel when left idling.  As with an automobile, 'jumper' cables are used to start a prime mover with dead batteries.  The difference is, they're on steroids.  When the start swith is engaged, so much current is being used that the cables often 'jump' when the juice is applied.  Only 72 volts, but drawing 800 amps.

Cylinder head water leaks are problematic as well.  When left standing for an extended period, these leaks can fill a cylinder with water.  When the engine is next started, broken rods or cranks are usually the result in these instances.

But, there are 'cylinder test c***s' and the rules require these to be opened prior to starting an engine.  These allow the cylinders to purge themselves at start-up and minimize the threat of potential damage.

The lubrication system is called a 'scavenging' type system that is different from the conventional lubrication systems in automobiles, and these provide for protection during start-up.

Answer 13

diesel idel does not use much fuel.