Leyland Sourer has
Page 24
If you've noticed an error in this article please click here to report it so we can fix it.
sophistication by Martin Hayes
A REMARKABLE LEVEL of cross-border co-operation by several leading European bus makers resulted in the production of the Leyland Saurer city bus released at the Geneva Show earlier this year and now in service with the Geneva municipal undertaking. I had an exclusive opportunity to drive one of the new vehicles in England last week.
The bus is unusual among designs for city service use in that it has a mid-underfloor-mounted engine which is partially encapsulated. This is a Saurer DIJ2KT turbocharged six-cylinder unit which develops 240 bhp. The other major running units — front axle, suspension and so on — are British Leyland while the integral body is built by DAB, Leyland's Danish subsidiary. There is an Eaton rear axle.
The vehicle I tried was a conventional single-decker with 29 seats and space for 73 standees though several of the 25 vehicles now in use are articulated versions.
An interesting feature of the vehicle is the transmission. This is a Self Changing Gears model with the C83 automatic control gear. Mounted on the transmission is a Telma 155 retarder which operates through initial pressure on the brake pedal.
On Leyland's figure-ofeight test track the vehicle gave a good account of itself and, not surprisingly with that engine output, proved very lively. Transmission changes were by and large quite smooth, and although it was possible to catch out the gear change by lifting off the throttle at a critical point, In automatic the top four ratios are used — all five can be engaged manually. Leyland engineers are considering fitting their own G2 transmission, or alternatively the C33 unit may be further developed to have a throttle dip facility.
Single switch
One part of future European legislation which will have a quite major effect on detail engine design is the requirement for a single switch to cut off fuel supply, stop the engine and switch on the hazard warning lights. The Saurer was the first vehicle I had come across with such a device fitted and most .effective it was. The engine actually did stop instantaneously. The electric switch activated a compressed air cylinder to cut the fuel.
On the test track I was impressed with the ZF power steering which left quite a lot of "feel" for the driver. However, this particular vehicle had non
standard dampers which allowed too much roll on fast bends and bounce on rough surfaces. These are soon to change.
The footbrake-controlled Telma was very smooth in operation and it was not until I switched it out of operation an apparantly standard facility on this vehicle that I realized how much work it was doing. On a greasy circuit at high speed, check braking with the full-air system called for a good deal more concentration than achieving the same retardation from the Telma.
The Leyland Saurer is estimated to cost £31,000 and at present its application is restricted to Switzerland. However, there is a possibility that it may have wider sales in Europe — though presumably this price level would have to be amended if large volume sales were to be expected.