Diesel Hydraulic Locomotives

[Harpo]

A lesson might be not to let the prejudices of the CME affect the choice of engine. In retrospect the Sulzer 12LDA28C was not as reliable as the EE 16CSVT!

Yes. The great Brush success story, nearly 800 locos needing re-engineering - 512 type 4s permanently derated to avoid them failing and 263 type 2s needing English Electric power units to rescue them and keep them operable.

 

[Prime586]

It is important to note, the WR hydraulics were not pure hydraulics, they were hydraulic-mechanical, pure hydraulics use hydro-static drives, hydro-static drive is a hydraulic pumped circuit driven by say a diesel engine, the pump pressurises hydraulic oil in the circuit which is fed to hydraulic traction motors creating propulsion, for hydrostatic drives, the pump is run flat out,by a diesel engine running at full rpm, control by swash plates to vary power to the hydraulic traction motors.
Western hydraulics employed a mechanical transmission with multiple gears over the speed range, recall the Hymeks on Lickey banking duties, at banking speeds, they would hunt between first and second gears back to first a risk to the transmissions, first gear was locked out to stop the hunting.
The Warships were known as camels, the mechanical gear changes very violent and alarming to the drivers, the roughness felt by the passengers.

See my post #52. The Voith transmissions used in the Class 22, 41, 43 and 52 had 3 speeds, but did not use gears. The speeds were produced by having 3 separate torque converters with progressively smaller impellers and turbines, with 'gear' changes being achieved by draining and filling the converters with oil in sequence (my post includes a link to a cutaway diagram of the Class 52 transmission).

Voith still produce this type of transmission for DMUs.

The Maybach Mekydro transmission used on the other WR diesels used a torque converter with conventional mechanical gears that were selected by clutch pawls attached to selector forks (like a racing 'dog' gearbox), which led to their harsh engagement.

 

[simonw]

Wasn't the Class 56 notoriously unreliable due to Ceausescu's Romania mucking the whole job up?

Hand built by candle light, is one description.

 

[E27007]

See my post #52. The Voith transmissions used in the Class 22, 41, 43 and 52 had 3 speeds, but did not use gears. The speeds were produced by having 3 separate torque converters with progressively smaller impellers and turbines, with 'gear' changes being achieved by draining and filling the converters with oil in sequence (my post includes a link to a cutaway diagram of the Class 52 transmission).

Voith still produce this type of transmission for DMUs.

The Maybach Mekydro transmission used on the other WR diesels used a torque converter with conventional mechanical gears that were selected by clutch pawls attached to selector forks (like a racing 'dog' gearbox), which led to their harsh engagement.

Thank you correcting my error about transmissions,
The Class 14 "Teddybear" diesel-hydraulic, were their transmissions by Voith too? Teddies and 08's worked the yard at Beechbrook Farm near Ashford Kent on construction work of HS1, For shunting work, the yardcrews preferred the 08 over a Teddy for ease of operation, the Teddy had to be coaxed to shunt, would that be the draining and filling of oil the Voith transmission torque convertors with each change of direction?

 

[norbitonflyer]

Yes. The great Brush success story, nearly 800 locos needing re-engineering - 512 type 4s permanently derated to avoid them failing and 263 type 2s needing English Electric power units to rescue them and keep them operable.

To be fair to Sulzer, they were not responsible for the problems with the Type 2s, whose original engines were Mirrlees (thus in-house, as Mirrlees and Brush were both part of the Hawker Siddeley Group) .

 

[E27007]

To be fair to Sulzer, they were not responsible for the problems with the Type 2s, whose original engines were Mirrlees (thus in-house, as Mirrlees and Brush were both part of the Hawker Siddeley Group) .

I do not believe BR ever truly found the right diesels for freight duties, a retired senior BR manager lives in my village, he said BR thought the 58s and 60s were wonderful, then not so wonderful when the V12 EMD 66's "into service" revelation what a diesel locomotive could be.

 

[Harpo]

I do not believe BR ever truly found the right diesels for freight duties, a retired senior BR manager lives in my village, he said BR thought the 58s and 60s were wonderful, then not so wonderful when the V12 EMD 66's "into service" revelation what a diesel locomotive could be.

59s were the revelation. 66’s a consolidation a decade later.

 

[Harlequinuk]

From my own understanding, the rebuilt mark 2 JVS12T were reliable; however the decision had already been made to reengine the class.

 

[Ziggy3legs]

Class 56s - now there's a book I could write!
Gas pipe for conduit, and when it had been cut during installation it wasn't de-burred internally with the result that when cables were pulled through the inevitable happened with damaged insulation and the resulting earth faults.
The staff worked 12 hour days or nights on a permanent basis, and as you say at certain times of the year as demand dictated could even be sent to work on farms!
They didn't have basic supplies like insulating tape, or taper taps for cutting internal threads so the Brush rep would go out there with bags loaded these (and probably more) items.
I was also told they dropped one in the harbour during loading but I never heard anymore on that.

 

[MicroLithium]

I was also told they dropped one in the harbour during loading but I never heard anymore on that

A class 70 was definitely dropped, bent, and written off

 

[Ayrshire Roy]

A class 70 was definitely dropped, bent, and written off

Written off by freightliner but returned to GE and is now a fully running test mule.
It still doesn't look quite square when you see it.

 

[norbitonflyer]

Written off by freightliner but returned to GE and is now a fully running test mule.

Was it actually written off by Freightliner, or was it still owned by GE at that moment? Not sure at what point in the delivery ownership passed from GE to Freightliner

(An important issue that is always specified in international trade, as it determines who is reposnsible for freight costs, customs duty, insurance in transit, etc.)

 

[Tetragon213]

A couple of years ago I was at the funeral of the former KX Divisional C&W Engineer (Pat Sumner) and David Russell, the DME who appointed him, was there. David was very frail - he died in April last year but as the ER CM&EE, he had to sort out the Romanian 56’s. He told me a a few things about them.

The build quality was uniquely bad. Stratford DRS had to give them to once over and, to give you just two examples, they found that the electrical conduit was actually gas pipe with solid connections and elbows and the axle box lubrication was actually swarf! Some internal equipment had “left hand” and “right hand” connectional variants.

Apparently there was a Brush rep on site in Romania but on some days/weeks the factory was empty. That was because the workers had been told to report to a shipyard to work on a ship or go on the land to collect in the harvest!

That is truly shocking, even by Eastern bloc standards! But it makes sense, considering how Ceausescu's Romania was pretty desperate for cash at the time and their industry wasn't fantastic to begin with.

 

[Harlequinuk]

Was it actually written off by Freightliner, or was it still owned by GE at that moment? Not sure at what point in the delivery ownership passed from GE to Freightliner

(An important issue that is always specified in international trade, as it determines who is reposnsible for freight costs, customs duty, insurance in transit, etc.)

It never left the dockside, and will never have officially arrived in Britain. It will effectively have been ‘lost en route’. The sling broke whilst the loco was still in the ship and it then fell onto the pontoon deck

 

[ac6000cw]

To the best of my knowledge, creep control was only possible with electric transmission. I guess though we’ll never know what the upper haulage limit of a single hydraulic loco could have been.

More modern, but the Voith Maxima 30CC and 40CC hydraulics from 2006 were rated at 519kN starting, 408kN continuous TE. They had single engine driving both bogies.
From the Wikipedia page re. the transmission:

The 'Turbo Split' LS 640 reU2 transmission allows for a separated traction and wheelslip control of each bogie, being the first locomotive series equipped with this new technology.

== Doublepost prevention - post automatically merged: 25 Jun 2026 ==

My point was that if you were going to have any kind of creep control (which is effectively a wheelslip elimination system) on a hydraulic drive then you would need independent wheels

Electric transmissions with creep control capability can still have occasional/brief normal wheelslip issues e g. when starting or when encountering patches of poor adhesion, but they are much faster at detecting and dealing with it.

One traditional strength of hydraulic loco drives is that all the axles in a bogie are coupled together, making slipping less likely than on a traditional DC-motored loco (where individual axles can slip independantly).

 

[Harlequinuk]

How does it compare to the system on the CLass 74? Said to be amongst the most advanced of time with automatic current regulation; wheel-slip detection and correction along with automatic camshaft control (from simon lilley book), meaning on freight it could haul heavier loads than expected

 

[Taunton]

Class 56s ... The staff worked 12 hour days or nights on a permanent basis, and as you say at certain times of the year as demand dictated could even be sent to work on farms!

Actually standard Socialist Europe approach. In the Soviet Union, at the same era, or even more recently, schoolchildren would be "volunteered" to get the harvest in.

 

[Prime586]

Thank you correcting my error about transmissions,
The Class 14 "Teddybear" diesel-hydraulic, were their transmissions by Voith too? Teddies and 08's worked the yard at Beechbrook Farm near Ashford Kent on construction work of HS1, For shunting work, the yardcrews preferred the 08 over a Teddy for ease of operation, the Teddy had to be coaxed to shunt, would that be the draining and filling of oil the Voith transmission torque convertors with each change of direction?

Yes, Class 14s used a smaller version of the Voith 3-stage transmission. They were designed for short trip working of wagonload freight between local yards, or from yards to private sidings (basically as a replacment for the GWR 0-6-0 pannier tank locos), not specifically for yard shunting like the Class 08 (the Class 14 had a top speed of 40mph, versus the Class 08's 15-20mph).

The electric transmission of a Class 08 meant it could be reversed almost at the drop of a hat. If you look at the diagram of the Class 52 Voith transmission in my previous post, the reversing mechanism is on the RHS side - there is a set of idler gears above the main output gears on the turbine shaft, and a mechanical selector fork with dog clutches on it is used to select between these gears for forwards and reverse. For a 'clean' direction change the turbine shaft needs to be almost stationary, which means having to bring the engine to idle, drain the 1st stage torque converter of oil and then refill it once the output gear for the direction has been selected.

This made yard shunting with a Class 14 a bit more cumbersome than with a Class 08, but it was not what they were primarily designed for.

 

[E27007]

We associate hydraulic locomotives with the Western region of BR, there is more, Colonel Fell, Ivatt and Fell locomotive 10100.
10100 was the Mark1, Fell designed a Mark2 which was not built, Mark 3 was DHP1, a locomotive project that was abandoned at the drop of a hat without a fair trial.

here is a link to Colonel Fell :
Colonel Fell, DHP1

 

[Grumpy]

We associate hydraulic locomotives with the Western region of BR, there is more, Colonel Fell, Ivatt and Fell locomotive 10100.
10100 was the Mark1, Fell designed a Mark2 which was not built, Mark 3 was DHP1, a locomotive project that was abandoned at the drop of a hat without a fair trial.

here is a link to Colonel Fell :
Colonel Fell, DHP1

One of my old work colleagues had ridden behind the Fell.
We were travelling behind a Hymek one day and he remarked that the Hymek "gear change" that could be felt in the train was just like the Fell.

 

[E27007]

We associate hydraulic locomotives with the Western region of BR, there is more, Colonel Fell, Ivatt and Fell locomotive 10100.
10100 was the Mark1, Fell designed a Mark2 which was not built, Mark 3 was DHP1, a locomotive project that was abandoned at the drop of a hat without a fair trial.

here is a link to Colonel Fell :
Colonel Fell, DHP1

On the modernisation of BR freight handing, greater adoption of hump shunting, work greater than the capacity of an 08, Fell designed a powerful trip loco and shunter which operated on the Fell principle of diesel engines coupled by differentials to give control of speed and tractive effort. The
loco would perform low-speed shunting duties on a single engine, two engines for faster trip working.

 

[Magdalia]

Actually standard Socialist Europe approach. In the Soviet Union, at the same era, or even more recently, schoolchildren would be "volunteered" to get the harvest in.

Go far enough back into history, and it happened here too.

In large parts of rural Scotland, the autumn half term holiday is still called tattie week, from the days when children helped harvest potatoes grown for seed.

Further south, in the days when London had a lot of manufacturing industry, factory workers would go on the train to Kent for hop picking.

These days, the Fens harvests that require lots of manual labour rely heavily on workers coming from Eastern Europe.

 

[Rescars]

Further south, in the days when London had a lot of manufacturing industry, factory workers would go on the train to Kent for hop picking.

Kept the likes of the K&ESR and the Hawkhurst branch busy during the season.

 

[Peter Sarf]

Actually standard Socialist Europe approach. In the Soviet Union, at the same era, or even more recently, schoolchildren would be "volunteered" to get the harvest in.

I believe in the UK the reason for the long summer holiday for schools was so that in the past the children (and their parents) would be available for the various crop harvests - nothing to do with it being a nice time for a holiday !.

 

[Harlequinuk]

I believe in the UK the reason for the long summer holiday for schools was so that in the past the children (and their parents) would be available for the various crop harvests - nothing to do with it being a nice time for a holiday !.

Historically yes but by the mid 19th century many children had no connection with farms , it would be because schools `back then` had poor ventilation and during the summer became ridiculously hot. So they took the hottest part of the year off, more so as both compulsory education (initially till aged 11 in 1893, then to age 12 in 1899 - and finally the Board of Education wanted it to be 14 in 1900) and a standardised curriculum ( Elementary Education Act 1880) were being introduced to bring literacy and numeracy standards up tor employment.

Sorry history lesson over.

 

[Acathater]

In Somerset it was blackcurrant and apple picking

 

[norbitonflyer]

It's also tied to the exam cycle being tied to the upper class (who were the only ones going to university) and the "London Season" followed by heading north for the shooting season, starting on the "Glorious 12th" (of August). So the universities and posh schools had a "long vac" in summer.
So public exams (GCE O and A level, Common Entrance, etc) were at the end of the academic year, in late Spring/early summer.

 

[Taunton]

In Somerset it was blackcurrant and apple picking

I think that should be blackberries - which grow wild at the roadside. Harvest Festival, a key point in Somerset church social calendars, is actually around full moon near 1st October - full moon to give light in the fields when working late. Traditional to have a form of foods collection at the church as part of this, which local farm labourers distributed to the elderly after the service, thereafter heading to the village pub for a continuing form of festivity, which the vicar wouldn't really approve of ...

 

[Clarence Yard]

It’s often forgotten that the twin engine hydraulics also played into the WR maintenance philosophy.

WR depots were expected to undertake major component changes, in complete contrast to the original ER philosophy, which was to concentrate on maintenance and minor work.

So while WR depots such as Old Oak Common had both jacks and substantial capacity cranes, older ER depots such as Finsbury Park had neither. If something serious happened there, it was originally envisaged that it would be a trip to either Doncaster or Stratford Works.

 

[Acathater]

I think that should be blackberries - which grow wild at the roadside. Harvest Festival, a key point in Somerset church social calendars, is actually around full moon near 1st October - full moon to give light in the fields when working late. Traditional to have a form of foods collection at the church as part of this, which local farm labourers distributed to the elderly after the service, thereafter heading to the village pub for a continuing form of festivity, which the vicar wouldn't really approve of ...

Nope
I meant blackcurrants, acres and acres of the things for Ribena. On the fruit farms around Martock, South Petherton, Stoke, and on towards Ilminster. Picked by the bucket load by teams of schoolkids and gypsys.