No it wasn't wrong as that is what has been said by Vivarail I do believe. Now tell me why you deem them and the whole conversion as 3rd rate
Presumably a maintenance regime tailored specifically to these specific engines will need to be devised, possibly involving rebuild or replacement at intervals... Information from Vivarail suggests they can be dropped out of a unit and replaced with a new or reconditioned example as a straightforward, simple and routine task... (But I believe all of this has been covered on here before..)
60mph trains replacing 75mph trains isnt a problem as long as the 60mph trains can cope with the services that they are scheduled to run on (just like it wasnt a problem when 75mph trains replaced 125mph trains on Northerns service from Preston to Hazel Grove!).
I would ask you to read posting # 956 on this thread by Greybeard33 that concerns diesel engine usage in its normal automotive life and a comparison of the operational requirements of same in a railway scenario.
The 150s were built as solid units but they've got to the age when either they need life extension work to continue in service or they need to be withdrawn. Northern unit 150135 spent 18 months out-of-service due to corrosion issues, which cast doubts over how long some of the 150s can remain service without major work.
Didn't they say they would be operating similar to 185's eco mode and being computer managed and not all working 100% of the time? Could also be using a battery to buffer the power and even out some of the demands.
But Diesel engines in road vehicles rarely spend extended time at maximum rpms the way they do in diesel rail vehicles ?
A serious question - is this a feature of Northern's peculiar brand of "maintainance" or a more widespread issue?
185s are overpowered for the work / timings they are on. What's the installed power on the d78s?
Heavy maintenance is the responsibility of the ROSCO not the operator.
Vinyls are applied by specialists - nothing to do with the operatorsThat I know but the actions of the TOC often don't help.. I'm pretty sure that I've seen mention of corrosion being exacerbated by badly applied vinyls for example...
More seats in third-rate refreshed elderly rail units
Well, bowing to your obvious superior knowledge of rolling stock provision, would you describe these units, with all that is stated needed to be done to them, as "first-rate" or "second-rate" units ?
I guess you've never been to Scotland
As to the 73s, Aslef have expressed fears about their use in "The Scotsman".
http://www.railforums.co.uk/showthread.php?t=105739
I can reassure you that the information provided by D60 above and before is correct. As to help, I have an assortment of links to "back up" what D60 says- as D60 says, Feb's Railway Magazine states that they are Ford diesel units, Modern Railway's Roger Ford says so in the December 2014 one, available online here, Rail Technology Magazine goes further to call them "Transit engines", and finally the "Land Rover Owner International" magazine/online thing calls them Ford Duratorq engines as used in the Land Rover Defender cars. According to RAIL, a company called "Revolve" (of Essex) is supplying the engine power modules [ref]. Rail Technology Magazine's Sam McCaffrey also partook in an interview with Vivarail where they described the new diesel engines as "two 3L Ford Diesel engines combining to create 400hp for each driving car, plus a modern alternator and inverter with an output of 750v DC, plus a compressor".
The "key figure" is also Adrian Shooter, the ex-boss of the rather successful Chiltern [ref here], so I suspect that he knows what he's doing.
jcc

It has been quite rightly said that it is far too early to make full assumptions as to the conversion worthiness and with this, I totally agree
I see, so you are happy for someone to claim that a conversion of 30 year old stock, with a low maximum speed and completely untested apart from computer simulations on a slow line (which apparently yielded a whopping 3 minute journey reduction), with a price tag somewhere between 1/3 to 2/3 of the cost of a new unit is going to be the best on the network? This doen't ring any alarm bells? You don't happen to work for DfT by any chance?
It's one thing to take the D stock convertions and pitch them as a cheap and cheerful solution for branch lines if Roscos/Tocs want to take a chance. But pitch them as the best on the network and try to make them sound like they are suitable for longer journies (the Country veversion with the 2x2 around tables configuration) and you are at best stretching the truth. Remind me never to buy a second hand car from them, or you for that matter.
Would properly refurbished D78s be the end of the world on such routes?
It takes a lot less power to keep a train moving than it does for a road vehicle of the same weight, so traditionally with rail diesel engines the problem has been frequent transitions between max power for acceleration and little or no power at other times. But this seems to have been a problem mainly for HSTs. The smaller engines on Sprinters etc seem to have been pretty reliable and these are similar to larger automotive engines.
Also the mechanical transmission on a road vehicle or the hydraulic transmission with lock-up on most DMUs means the engine has to be near maximum revs at maximum speed, because it is directly geared to the wheels. D78 will have electric transmission which means the engine can operate at the optimum speed to produce the power required at any particular time.
I thought that on diesel electric units, that it was the same that full engine rpms are used. Class 22x units springs to mind.
Are people in Manchester really getting irate at the prospect of cascaded trains, or is it just interested parties? I've discussed rolling stock cascades with various people on Merseyside who have seemed uniformly enthusiastic about the upcoming class 319 trains especially with the northern refresh. If I asked them if they were bothered about the trains being hand me downs I generally just got a "heard it all before" roll of the eyeballs (although someone did quip that he thought some elsewhere in the region might believe they are too good now for cascaded trains!)I’m not jumping to conclusions about what standard the refresh will look like in reality (I’m ignoring the “artists impressions” on the website) – I was just surprised that you were.
Born there, lived half my life there, thanks...
...but other than predictable Union sabre rattling, the terms and conditions of the Scottish franchises (ScotRail and Sleeper) haven’t seen anything like the complaints that you typically see from north (west) England about things.
That’s the point that I was making – people in Dundee aren’t wailing about getting 1970s “London rejects” to replace their post-privatisation DMUs but people in Manchester are wailing about getting 1980s “London rejects” to replace their 1980s DMUs (319s replacing 150/156s). Those north of the border are less hysterical about such things.
Very interesting post, thanks
I agree, it’s far too early to reach conclusions about these units, which I was surprised to see a learned member of the Forum describe them as “third rate” refreshes when we don’t know how they’ll look.
I’m not losing any sleep over what a PR mouthpiece claims – what matters is whether this stock is suitable for whatever services are found for it (if any) – be that in Thurso or Penzance.
Since there are plenty of “slow” lines in the UK, which tend to require subsidising, I don’t think it’s a bad idea to investigate whether we can convert stock to run on these services (which would free up the 75mph stock on those lines to lines that do require faster speeds).
Of course it’s “untested” (other than in computer programming terms), because they aren’t ready yet. Similarly, 345s, 700s, 800s and 801s are “untested” on British tracks.
Of course the PR people are going to promote them as being the best, that’s what they do – I’m surprised that you are surprised by this! They’re hardly going to say that TOCs would be better hiring more Sprinters, are they?
As for the idea of D78s with “universal” toilets, 2+2 seating, tables... there are some longer distance lines (Heart of Wales, Far North, Kyle, Cumbrian Coast...) where many passengers are travelling long distances but there’s no need for running at over 60mph.
Would properly refurbished D78s be the end of the world on such routes?
But the maximum gross weight of a fully loaded Ford Transit van is about 5T. According to the RTM interview with Adrian Shooter, a 3-car D78 will weigh about 75T (25T per vehicle) plus, say, 25T of passengers, i.e. 100T gross weight, divided between 4 engines. Therefore each engine will have to accelerate about five times more mass in the train than in the van - much higher loading.It takes a lot less power to keep a train moving than it does for a road vehicle of the same weight, so traditionally with rail diesel engines the problem has been frequent transitions between max power for acceleration and little or no power at other times. But this seems to have been a problem mainly for HSTs. The smaller engines on Sprinters etc seem to have been pretty reliable and these are similar to larger automotive engines.
Also the mechanical transmission on a road vehicle or the hydraulic transmission with lock-up on most DMUs means the engine has to be near maximum revs at maximum speed, because it is directly geared to the wheels. D78 will have electric transmission which means the engine can operate at the optimum speed to produce the power required at any particular time.
A 2/3 car D78 will have twice as many engines as a conventional 2-car DMU. So, unless the engines are twice as reliable, engine failures in service, requiring unscheduled maintenance, will be more frequent. Scheduled maintenance is also likely to be more costly because there will be double the number of engines to work on.
But the maximum gross weight of a fully loaded Ford Transit van is about 5T. According to the RTM interview with Adrian Shooter, a 3-car D78 will weigh about 75T (25T per vehicle) plus, say, 25T of passengers, i.e. 100T gross weight, divided between 4 engines. Therefore each engine will have to accelerate about five times more mass in the train than in the van - much higher loading.
A 2/3 car D78 will have twice as many engines as a conventional 2-car DMU. So, unless the engines are twice as reliable, engine failures in service, requiring unscheduled maintenance, will be more frequent. Scheduled maintenance is also likely to be more costly because there will be double the number of engines to work on.
But the maximum gross weight of a fully loaded Ford Transit van is about 5T. According to the RTM interview with Adrian Shooter, a 3-car D78 will weigh about 75T (25T per vehicle) plus, say, 25T of passengers, i.e. 100T gross weight, divided between 4 engines. Therefore each engine will have to accelerate about five times more mass in the train than in the van - much higher loading.
A 2/3 car D78 will have twice as many engines as a conventional 2-car DMU. So, unless the engines are twice as reliable, engine failures in service, requiring unscheduled maintenance, will be more frequent. Scheduled maintenance is also likely to be more costly because there will be double the number of engines to work on.
These units may have low leasing costs (although the cost of the conversion will have to be recovered over a relatively short service life), but what matters to the TOC is total operating cost, taking account of maintenance costs and fleet availability.
My point was that engine design is inevitably a compromise between various conflicting requirements. Automotive engines are optimised for automotive requirements, which, as you rightly point out, are quite different to those for a DEMU engine. A D78 engine will spend most of its life alternating between periods of constant speed, maximum power operation and periods at idle/shutdown. Maximum power means maximum mechanical stress and maximum component temperatures. Sudden cutback from maximum power to idle/shutdown causes high thermal stress, particularly on components like turbochargers. Purpose-designed railway diesel engines are optimised for high reliability and long intervals between overhauls with this type of duty cycle.What you've missed in your calculation is that in the Transit the engine is driving the gearbox directly - a mechanical transmission.
However in the proposed D78 the engine is there to drive an electric motor which will provide the transmission - so the two are not directly comparable and the stress on the engine quite different.
It's worth noting that the engine appears to be de-rated some 20% from its lowest rating in automotive applications, at least in the Land Rover / Citroen specifications (I cannot find details of the Transit use.) Railway cycling as described above has caused problems in other engines adapted for rail use, but these often have been larger engines adapted from marine or stationary generator applications. Other engines adapted from road use have generally fared well - like rail, road use is constantly varying load, in fact much more so than rail.My point was that engine design is inevitably a compromise between various conflicting requirements. Automotive engines are optimised for automotive requirements, which, as you rightly point out, are quite different to those for a DEMU engine. A D78 engine will spend most of its life alternating between periods of constant speed, maximum power operation and periods at idle/shutdown. Maximum power means maximum mechanical stress and maximum component temperatures. Sudden cutback from maximum power to idle/shutdown causes high thermal stress, particularly on components like turbochargers. Purpose-designed railway diesel engines are optimised for high reliability and long intervals between overhauls with this type of duty cycle.
I might be proved wrong, but I think there is a risk that the automotive engine will turn out to be unreliable in the D78 application, and expensive to maintain.
If Wikipedia is to be believed, Vivarail has selected the 3.2L Ford Duratorq TDCi inline-five turbo intercooled engine, with a nominal rating of 200hp, used in the Ford Transit and Ford Ranger.It's worth noting that the engine appears to be de-rated some 20% from its lowest rating in automotive applications, at least in the Land Rover / Citroen specifications (I cannot find details of the Transit use.)
My point was that engine design is inevitably a compromise between various conflicting requirements. Automotive engines are optimised for automotive requirements, which, as you rightly point out, are quite different to those for a DEMU engine. A D78 engine will spend most of its life alternating between periods of constant speed, maximum power operation and periods at idle/shutdown. Maximum power means maximum mechanical stress and maximum component temperatures. Sudden cutback from maximum power to idle/shutdown causes high thermal stress, particularly on components like turbochargers. Purpose-designed railway diesel engines are optimised for high reliability and long intervals between overhauls with this type of duty cycle.
I might be proved wrong, but I think there is a risk that the automotive engine will turn out to be unreliable in the D78 application, and expensive to maintain.