Engine punking on the daily commute

A refurbished 150 Sprinter class (Photo : Peter Skuse)

The other day, I started to wonder about what engines powered my commuter train. A hundred years ago they would have been steam engines, maybe a steam rail motor but more likely powered coaches with a cheeky tank engine.

Nowadays they are powered carriages that divide and multiply - as one literary person once complained - like worms. If anyone knows who said this let me know. I think it's a great quote.

The worms I ride on are usually Class 158 or 150s Sprinter units but sometimes we get 155 or 153 Class units, either singly in pairs.

Class 150s and 158s all have a single Cummins NT355 or NTA355 water-cooled six cylinder diesel engine to each unit. Mounted on their sides under the floors of the passenger saloons, these drive the bogies through a hydraulic final drive. These put out either 325 or 400 bhp at 1800rpm. Bore and stroke is 140 x 152mm (5.5 x 6 inches!) for a capacity of 14 litres (I make it 14039cc) or 855 CID.

Class 158 units are a bit posher than we are used to. I particularly appreciate the extra legroom (Photo : Adam Bryant)

NT denotes a turbocharged installation while NTA versions get an intercooler.

There are also Class 155 and Class 153 units, again all powered by our new best friend the Cummins NTA355. The 155s feel quite old now and were built by Leyland Bus at Workington between 1987 and 1988 when British Rail replaced its First-Generation DMUs.

Class 155s come in all sorts of different liveries. This one belongs to Northern Rail and shown at Leeds (Photo : Peter Skuse)

Class 155s are single version of the 153s and were intended for rural areas where volumes are low but they can get very crowded and you wonder what sort of maximum loading the powertrains are designed for.

When these Leyland National buses came out they looked so new and fresh. I particularly associate them with Western National livery, as seen here. Photo : Graham Richardson

I have spotted the old Leyland logo inside inside 153s and 155s from time to time and remembered that, backalong, there was a link to Leyland National single-decker buses. Great things were expected of these busses and they looked like no other when they came out.

I mean that in a good way - I really liked the look of them back in 1972, with their heater/ventilation pod on the roof at the back, and still do. They looked like a space age bus to me as a nascent (good word that) industrial designer. The panel fit looked very considered to me and they sat on the road well. Michelotti had a hand in the styling - he was already styled many Triumphs. (Ha! See what I did there?) Subsequent buses have been just square blocks to look at.

The Leyland National buses had Leyland engines, mounted horizontally and under the floor, with integral heads but they proved to be unreliable and unpopular. Eliminating the head to block joint seemed a good way of avoiding gasket problems and harked back to classic early engine architecture but the turbocharged 510 series engine was heavy in fuel and could smoke badly. Bore and stroke was 118 x 125mm for a capacity of 8202cc or 500CID and it put out 170bhp @ 2600rpm and 375 lb ft at 1800rpm. A new design of air suspension and power assisted rack and pinion steering competed the package.

The common link between the railbus and the, er, bus bus is in the modular construction, which caught the eye of British Rail engineers. This was developed by Pressed Steel, another part of the BL empire and consisted of powder coated steel pressings assembled into discreet sections or bays. Each bay featured a ring structure of pressings and, together with the integral roof and substantial underframe, provided a very rigid structure that could also be easily repaired.

The family resemblance is obvious on these Class 141 pacer units (Photo : Hgt)

The first railcar incarnations, such as the Class 141s and 142s bore an obvious family resemblance to the road buses but didn't look so groovy, especially as the front ends had to conform to lighting and coupling layouts. They pre-date my days as a commuter. They also had Leyland TL11 engines. 142s with different front and rear designs saw the introduction of a six-cylinder Cummins engine, in the form of an LTA10 (125 x 136mm for a capacity of 10014cc) putting out 225bhp.

The standard Leyland National window bays have evolved over time and now the origins are hidden. The lightweight that was of benefit in road buses has hampered rail adhesions. Often they can be felt be sliding under braking as they come into Menheniot and other wooded section. Leaf mould can make the rails very greasy and it's difficult to get the power down sometimes as we pull away.

This is one of our local Class 153s at Par (Photo : Geof Sheppard)

Fortunately, the trains are usually quite full - overcrowded even - so, as we sing songs in a brave example of blitz spirit as we stoically rise to the challenge of the wrong sort of snow or other slipperiness, the more of us making merry adds to ability of our friendly Cummins engines to get the power down.

I await the next railcar developments with interest. These are old designs now and are showing corrosion despite the revolutionary steel and aluminium treatments. Some have been refurbished and fitted with Tardis like lavatories that can be used by less able bodied commuters.

I will continue to commute by rail for the foreseeable future for all sorts of reasons but mostly because its convenient and cost effective. Although the units are old and noisy and past their best, I expect any new units to supplement them. There simply aren't enough of them and the ones we have are used hard. We had a late train the other day and the excuse was "unexpected levels of mechanical failure." I wonder about the planned maintenance of these units and wonder if it's been treated as management risk i.e. they ignore maintenance until there's a failure. Then they attempt to manage that failure as it arises.

I am not sure to what high performance automotive applications these Cummins engine could lend themselves. Lend me one and I might have a go. Maybe a high performance Leyland National?

It will be interesting to see if the tractor pulling boys adopt them but the underfloor configuration doesn't help.

In the meantime I will enjoy them in their intended application.

PS I made that bit up about the blitz spirit and the singing. Everyone gets very cross and complains bitterly but we all know its profits before passengers.