How long can a train engine safely run for?

[Mitchell Hurd]

Good morning. Now I thought I'd create this kind of thread. Basically, I'm quite keen to know how long a diesel train engine can run for with people onboard.

I'm trying to ask this as delicately as possible - the reason is if you're say on a DMU (or in an IET carriage with the engine underneath) yes they're might be a serious problem on the line, a power failure, signalling failures / problems or the train might have broken down.

I know an engine in a road vehicle is very different to a train engine but if I understand, not great to run a car engine for hours I guess with people inside.

Just incase I'm caught up in a very heavy delay, how long can a train engine be on for without causing passengers to be unwell?

Sorry I know it's a strange one I'm asking but I thought I'd check.

It must be fine though because when I've read CrossCountry Voyagers or other TOC's DMU's being severely delayed, it seems obvious that train engines are designed to run for very long periods of time. With a loco-hauled train or HST, you're fine as the passengers are sat in a train with no engines running - in Mark 1 coaches on preserved railways its even better as there's no motors or diesel engines running underneath.

It's a tricky one I know - basically you need diesel engines to run to provide what you want in a hotel: heating or air-conditioning depending on the weather, toilets, lighting. I understand that starting a train up requires 10-15 minutes of not moving to allow the train to have enough air to move.

If this helps, going back to the 18/02/19, I caught the 15:30 from Bristol Temple Meads to Didcot Parkway (10-car IET) which came in about 14:40. At around 14:50 I was allowed on - I was happy for the engine to run as it meant I could be in somewhere warm and email CrossCountry about my 2 train trips that morning. I can't do it with cold fingers so an IET with it's good heating system was very welcoming indeed .

If I've answered my own question in train engines being designed to run for long periods of time then tell me.

 

[bengley]

There are no restrictions

 

[Mitchell Hurd]

There are no restrictions

Right, thanks !

 

[AM9]

There are no restrictions

I assume that with the Hitachi Bi-Modes, in the event of an extended delay with little prospects of an early passenger release, the hotel services can be provided by a single genset. Therefore, fuel reserves could last for days if absolutely necessary, although the retention tanks filling might cause a few problems.

 

[Bletchleyite]

I know an engine in a road vehicle is very different to a train engine but if I understand, not great to run a car engine for hours I guess with people inside.

Subject to servicing intervals and how a very long idle might affect them, there is no safety issue with leaving car engines running for any length of time. The reason they say to turn them off if forced to sleep in a car is that nobody is monitoring to ensure e.g. there was no accidental fire.

 

[aleggatta]

I would probably also add, that with cars if queueing you have another in front of you idling away, with its exhaust close to your air intake, so the recommendation to turn off the engine would probably also be taking into account the prolonged degradation in the quality of air being created, and generally by turning the engine off turns off the ventilation(in most cases) and prevents the nasty gases being brought into the cabin.

trains are slightly different in that the supply air and exhaust air are normally far enough apart that this isn’t an issue, also with the advent of air conditioning less ‘fresh’ air has to be brought into the cabin so gases have more chance to stay outside the vehicle.

 

[talltim]

I’m sure I read about an 08 that had its engine running for a couple of years because they knew if they shut it down they’d never get it restarted.

 

[dk1]

Although we are advised to shut them down, class 08 shunters have been known to tick over for days at a time.

 

[cactustwirly]

Subject to servicing intervals and how a very long idle might affect them, there is no safety issue with leaving car engines running for any length of time. The reason they say to turn them off if forced to sleep in a car is that nobody is monitoring to ensure e.g. there was no accidental fire.

And the engine will burn through a lot of fuel if sat idling for a long time as well.

 

[squizzler]

I know an engine in a road vehicle is very different to a train engine but if I understand, not great to run a car engine for hours I guess with people inside.

Somebody should tell that to various motorists I've had the misfortune to be subject to who think it is okay to leave their engine idling outside premises I've worked in when their passenger goes in for what often seems to be a working lunch, judging by the time taken for them to re-emerge. It isn't. I have actually attempted to broach the subject by suggesting they should speak to their mechanic if they cannot easily turn it off and back on again as required.

Whilst the railways came to internal combustion about fifty years after motorists were doing it and will probably move onto other things sooner, they should still as an industry be as conscientious of only running their engines when required for useful work as people rightly expect from the motorist.

 

[bastien]

Somebody should tell that to various motorists I've had the misfortune to be subject to who think it is okay to leave their engine idling outside premises I've worked in when their passenger goes in for what often seems to be a working lunch, judging by the time taken for them to re-emerge. It isn't. I have actually attempted to broach the subject by suggesting they should speak to their mechanic if they cannot easily turn it off and back on again as required.

Whilst the railways came to internal combustion about fifty years after motorists were doing it and will probably move onto other things sooner, they should still as an industry be as conscientious of only running their engines when required for useful work as people rightly expect from the motorist.

Yes but if you leave the engine running, you're not actually parked on the double yellow, right

 

[Lewlew]

Yes but if you leave the engine running, you're not actually parked on the double yellow, right

Also, don't forget that hazard lights make you invisible so you can stop wherever you want.

 

[Bletchleyite]

And the engine will burn through a lot of fuel if sat idling for a long time as well.

It will, but if that was the only downside e.g. in the event of a mass motorway stranding in cold weather it would be preferable to people being too cold.

 

[73001]

I'm sure I read that in "ye olden days" some of the big diesels were left ticking over for days when the weather was really cold. The damage caused by freezing engines or the hassle of trying to start them was considered much more than any fuel or environmental concerns.

 

[AndrewE]

I'm sure I read that in "ye olden days" some of the big diesels were left ticking over for days when the weather was really cold. The damage caused by freezing engines or the hassle of trying to start them was considered much more than any fuel or environmental concerns.

except that a cold idling diesel power unit is vulnerable to fuel dilution (of the lub oil.) The fuel doesn't burn fully in the cylinders, condenses and gets mixed with the oil, so that when it is powered up the bearings don't get the lubrication they need and you have brought forward your overhaul date. Much better to get them hot through, then shut them down for a few hours.

 

[robbeech]

With older engines the varying temperature of various components on an idling engine for prolonged periods can cause a few issues. Expansion of parts with the heat vs not other parts can cause oil to seep past piston rings for example. The short term result of this is a notably increased smoke output for a short while when then engine speed increases the next time, this clears up after a couple of minutes. Longer term issues can include premature wearing of these components and of course oil usage. It's likely not something they worry about too much. It is very common on some high mileage diesel cars/vans, notably early Diesel Landrovers and anything with the 5 Cylinder Ssangyong OM622 engine fitted to many of their own cars and the first variant of Mercedes Sprinter vans.

 

[Cowley]

I'm sure I read that in "ye olden days" some of the big diesels were left ticking over for days when the weather was really cold. The damage caused by freezing engines or the hassle of trying to start them was considered much more than any fuel or environmental concerns.

Add weak batteries (not helped by sub zero temperatures) to that list. Plenty of diesels in the 1980s (including DMUs) we’re left ticking over during the night in cold weather to avoid the trouble of them not starting in the morning.

 

[Bald Rick]

Many ‘rail’ engines also have Marine applications. The Valentas inside the original HSTs also saw service in Royal Navy aircraft carriers, and they could be running for weeks at a time.

 

[Cowley]

Many ‘rail’ engines also have Marine applications. The Valentas inside the original HSTs also saw service in Royal Navy aircraft carriers, and they could be running for weeks at a time.

This all begs the question - What’s the longest an internal combustion engine has ever run for in one go..?

 

[ijmad]

This all begs the question - What’s the longest an internal combustion engine has ever run for in one go..?

There is a Bessemer 25HP engine pumping oil in the hills of Pennsylvania that supposedly has been in running continuously since 1899.

 

[cjmillsnun]

Many ‘rail’ engines also have Marine applications. The Valentas inside the original HSTs also saw service in Royal Navy aircraft carriers, and they could be running for weeks at a time.

They weren't idling for that time though...

 

[IJMOK]

Look up Operation enduring freedom, not a train, and not a diesel engine but it shows how a well thought out plan can keep an engine running to cover vast distances.

After 44hours in the air and numerous refuelling’s a B2 was kept running whilst the engines received new oil, the toilet was sorted out and a bit of food was placed on board, and she was sent on her final leg home,

 

[AndrewE]

With older engines the varying temperature of various components on an idling engine for prolonged periods can cause a few issues. Expansion of parts with the heat vs not other parts can cause oil to seep past piston rings for example. The short term result of this is a notably increased smoke output for a short while when then engine speed increases the next time, this clears up after a couple of minutes. Longer term issues can include premature wearing of these components and of course oil usage. It's likely not something they worry about too much. It is very common on some high mileage diesel cars/vans, notably early Diesel Landrovers and anything with the 5 Cylinder Ssangyong OM622 engine fitted to many of their own cars and the first variant of Mercedes Sprinter vans.

I think that first bit is what leads to fuel dilution (although I doubt whether differential expansion is to blame) but the plume from the exhaust is condensate being boiled off as the exhaust pipes heat up. Made up of vapourised partially-burnt fuel, water condensate and lots of nasties like acrolein (and sulphur and nitrogen oxides.)

 

[class 9]

Most operators have an idling policy, this is if a train will stand for more than 15 minutes, then the engines must be shutdown.

 

[Cowley]

There is a Bessemer 25HP engine pumping oil in the hills of Pennsylvania that supposedly has been in running continuously since 1899.

That’s very interesting thanks for that.

 

[Jozhua]

I assume that with the Hitachi Bi-Modes, in the event of an extended delay with little prospects of an early passenger release, the hotel services can be provided by a single genset. Therefore, fuel reserves could last for days if absolutely necessary, although the retention tanks filling might cause a few problems.

Considering the average wait time to evacuate or rescue a train currently in the UK, a few days worth of hotel power whilst idling seems about reasonable