Is it normal for a train's exhaust to be thick black and flames coming from the exhaust pipe?

Question

A few days ago, a freight train passed by. The smoke coming from the exhaust was thick and black, and it didn't look normal. As it passed, I could see flames shooting up through the black smoke. Was there a problem, or is that normal?

Answer 1

It depends. As with most things there are variables to consider.

Not knowing the type of engine you saw, there is a possibility this was normal, but I doubt it. There is a class of engine, SD-9, where this was expected behavior when in a slow, drag situation. There are not many of these still in service but, they are not turbo-charged as most newer equipment. EMD designed a 16 cylinder diesel prime mover that were equipped with "roots blowers". These were gear driven. In a long, slow climb up a grade, for example, when they were taxed it was common for them to "hunt", meaning slight differences in engine RPM, even though the injector racks were still at full rack. This caused a drop in intake manifold pressure, and as a result unburned exhaust gasses would pour from the stack, black, with occasional flame.

EMD prime movers, for at least 35 years, have incorporated a turbo-charger, but it is a hybrid. Most turbo-chargers run off engine exhaust. The EMD's were gear driven, through run five, and exhaust driven in run 6, 7 and 8. So, they were a cross between a blower and a turbo-charger.

These are equipped with a clutch, to disengage the geared portion of the blower when the turbo kicked in. When these clutches malfunction, usually due to no more than needed maintenance, or replacement, the turbo "stalls", with a loud, impossible to describe "chirping" noise, accompanied by the thick. black smoke and the flames out of the stack. This is caused by the same mechanics involved with the blown engines. Full rack, choked air intake.

The prime movers for the GE locos are blown. If there is thick smoke and flame coming from one of these, there is a very serious problem, but nothing that would cause a derailment or anything along those lines, but this engine has heavy maintenance in its near future.

The more likely outcome of a stuck injector is when the throttle is returned to idle, which unloads the engine, and the stuck injector would very quickly run the engine into overspeed. which is when it would automatically shut down. This is not as uncommon as it may sound, but I would rule it out in this instance, since the train was under power when you saw it.

Good question. You are very observant. Which means you probably pay attention when crossing railroad tracks in your car. This is a good thing, and you would do everybody a favor to let them know to do the same. Despite evryone's best efforts, grade crossing fatalities continue to rise. Pass this along. Each and every one is 99.99% avoidable.

Answer 2

The black smoke is normal when the train is loaded heavy and possiably pulling a grade. the operator has the accelerator wide open poring the fuel into the combution chamber. not enough air is entering the chamber to burn all the fuel that is being delivered. thus unbrunt fuel = thick black smoke. As for the flames (unless that engine has aftermarket flamethrowers on the exhaust) that is indeed a problem. The turbo might have broke causing the flames from the combustion chamber to excape directly out the exhaust pipe. (the exhaust manafold to the the pehaust pipe outlet is not very long.) I've had that happen to me on a 18-wheeler.

Answer 3

Thick smokey exhaust is actually quite common with older General Electric products as a result of turbo lag, and a host of other issues... Flaming stacks, although not as common, do happen when heated, unburnt fuel comes out the stack, mixes with the oxygen and "poof" insta-flaming stack. All this, in a cloud of black carbon smoke because there isn't enough oxygen being put into the engine for equal combustion.

Smoke and the occasional flame are not good, although they can be a normal occurance - it won't always cause damage or be a sign of major problems...the major problems start when the flames don't go out or when its a result of the engine spraying hot oil where it shouldn't be!!

I have caught heavy smoke from locomotives routinely and the occasional flame does happen without further incident usually lasting all of 5-10 seconds.

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The second two pictures (at Willimantic) that I linked, were a result of the engineer "notching it up" on a grade...45 or so loaded coal cars in tow.

Answer 4

Would depend on the class of power.... an old B36 GE might have a cracked piston crown.. If it was a Dash 9 GE it may be a cracked injector tip.. Modern EFI GE engines..(electronic fuel injection) will sometimes do this if an intake seal blows out causing a drop in turbo pressure.... Fact is there are many reason for this to happen...might be a seal going bad in the turbo...What ever the reason... Sounds like money in my pocket...:)

Answer 5

no, not normal at all, in cases like that, they use the engine until it reaches a yard that they can set it out in and fix the problem. assuming it is a modern diesel, it surprises me that the flames would make it past the turbocharger. possibly a bad injector, but I'd have to look at it to tell ya.

If the engine however was an older one made by ALCO (American Locomotive COmpany), it may be very normal, lol

Answer 6

cwrrailfan was right, this is a major problem, it usually means that the locomotive has a clogged injector, here where i live in Amarillo, TX, we had a locomotive completely burn up because one of the fuel lines was clogged. If left aone too long it could cause the entire engine to engulf in flames. "besides from what ive seen Norfolk Southern EMD's have a horrible problem with this"

Answer 7

its because of the burnt fuels... diesel is just the ropduct we get from one of the purification stages of crude oil.. which is nothing but a fossil fuel... the general content of the fossil fuel is carbon.. so when burnt to derive energy from it we get carbon as the byproduct.. thats the reason you can seen thick smoke arising form the exhaust

Answer 8

they call it pouring the coal to it.It only does that when they are accelerating.All diesel engines do it.Now days with electronic controls this is under control and not to noticable.Black smoke is unburned fuel there isnt enough air in the engine to burn it all.

Answer 9

I have had it happen with a bad turbo on a GE engine.........

Answer 10

normal.......... they generate a huge amount of energy and power/torque.......... and that equals a whole lot of heat.