A lack of power
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The Bedford TL has a power problem in the opinion of Bill Brock. Its lightly turbocharged engine makes it better suited to town running than rural rides
I MORE normal times it might lye been a logical progression r Bedford's TL introduced in 180 to have replaced the TK nge.
However, Bedford, in its wis)m, has chosen to produce )th in parallel while the more isic TK remains a viable propoLion.
Differences between the odels in the same weight class e small. The TL has a tilt cab hich is larger and heavier than e fixed cab of the TK. Much of e extra weight is offset by the ■ e of tapered leaf front springs Id by including tubeless radial y tyres to the standard speci;ation.
At 7.5 tonnes gross there is ill a payload penalty of about 6kg (2551b) which for our test 'hide gave a body/payload ipacity of 4.955 tonnes.
A lightly turbocharged 3.6 litre 20cuin) Bedford engine rated 53.9kW (72bhp) and giving a power to weight ratio of 7.1kW/tonne (9.76bhp/ton) (which, if applied to a 32-tonner, would be considered adequately powered) is quite meagre compared to the power and output of Bedford's 214 petrol engine and to other current diesel-powered 7.5 tonners.
This vehicle, though, was specified for town delivery work where acceleration performance and top speed are not paramount. Other engine, gearbox and rear-axle ratios are available and it is important to get the right mix to suit a particular type of operation.
It was quite clear that this vehicle was not specified for motorway running. A top speed of only 87 km/h (54mph) gave slow journey times over the first section of our route into Wales but because the engine had to work hard the slow speed was not compensated for by the fuel returns.
Continuing on our way after the fuel stop at Aust in heavy rain we passed through the toll at the Severn bridge.
As bridges are an intrinsic part of the country's road network, the toll seems an unfair burden on local operators who may go back and forth several times a day and have to pay this additional charge each time they cross.
It should not be necessary for the motoring public at large to pay extra while large sums of the road budget remain unspent year after year; the surplus 1981/82 figure alone of £82 million would be sufficient to pay off the cost of a recently built Humber bridge.
On the A-road section the 40mph limit could not be maintained where the road began to climb towards Monmouth or later in the hilly sections of the Welsh countryside. Where it became necessary to change down from top gear, the maximum speed in 3rd reduced the vehicle to a slow, laboured climb.
Power steering gave a good feed back to the driver through the steering wheel and the light control made tight manoeuvring an effortless exercise.
In-cab-noise was not obtrusive. The change to pendent pedals allows a floor pan design free of the small holes which let
the noise seep through from the engine compartment. The gear lever is mounted on a sprung island and its convoluted rubber, surround, adequately seals when the cab is locked in the down position, and a rubber collet joining top and bottom of the lever stops any harsh metal to metal vibration being transmitted.
Overall cab dimensions of the TL are greater, though still narrower than full width, and outwardly is similar to the TK in respect of the step arrangement and wheel arches. Rubber mat ting extends across the floor from door to door where it meets flush to the shallow lip, preventing a clean sweep out of any rubbish. Fuller width at shoulder height allows comfortable seating for two passengers and the driver.
A higher roof gives 1.07m (42in) from seat cushion to roof lining and allows room for a deeper windscreen. All-roundvision provided by door and rear-quarter panel windows is broken only by narrow screen pillars, panels immediately behind the door and at the centre of the rear panel. Just as impor tent for town deliveries is the height of the front screen which permits an upward line of vision to see shop namefronts, and traffic lights.
The small, unsprung driver's seat, with its thin sqab and low back, became uncomfortable after just a couple of hour's driving. A suspension seat can be specified but was not fitted here. Gear-changing should have been a simple enough operation but a positive movement was needed across the gate in selecting the right slot to find second.
Over half of the journey was in rain so the windscreen wipers were put to good use clearing a large portion of the front screen but leaving a gap of six or so inches on the nearside to dirty up.
The heating ventilation system controlled by three simple levers kept the inside free of condensation. Opening querterlights in the door allow an extra flow of fresh air, but, when closed, failed to exclude the wet. It was only a slight leak, but enough to form a pool beneath the driver's feet.
Behind the seats, Bedford has improved the shelf which has become a singular feature of the Bedford middleweight range. It is an ideal place to stow light personal effects and even paperwork, and the area above it provides an extra dimension the inside of the cab.
Two shallow shelves abo the windscreen are just t enough to contain maps and c livery notes. Wide doors and low step gave an easy entry ar with just the short gearsti protruding a few inches abo the seat squabs, cross-c€ access is relatively unob tructed, which allows kerbsil dismounting in busy streets.
The minimal instrumentatil is poorly distributed across it dashboard with engine temper ture, fuel, and air pressu gauges grouped together in tl one unit and the tachograi located on the other side of ti steering wheel.
Column-mounted controls 1 windscreen wiper lights, dirt tion indicators and haza warning lights are all close hand. The park brake, located the right of the driving seat, stubby, about hand size, has short movement and activat the release without any appi iated delay in the system.
The steering column incorpoates two universal joints below he retaining bracket and beause it is anchored to the cab Ind not to the chassis it is deigned to collapse in the event of ,n impact.
Externally, the cab presents :lean, non-aggressive lines, but vhile the almost-flush door landles are recessed, the front lirection indicator lamps stick )ut on rubber mounts.
Fifty degrees of tilt exposed he whole of the engine cornmrtment but it should only be lecessary to raise the cab up for najor maintenance. Normal Jay-to-day servicing can be ..tompleted using the TK-type linged balances either side at he rear of the cab giving access lo oil and coolant.
Torsion bar counter-balancing assists the manual cab tilt, which is locked safely at the maximum angle by an over-centre strut, without having to disconnect either steering wheel or gear lever.
The overall fuel consumption of 16.74I1t/100km (16.87mph) was little to write home about but might well be improved with one of the higher axle ratio options. However, with the limited output of this lightly turbocharged engine which provides only 5kW (7bhp) more than the naturally aspirated 220 dieselengine, power would remain a problem. Bedford are believed to be looking to produce a bit more power from this engine and we may see the result of more forceful turbocharging a little later this year.
Long, tapered leaf springs give a ride which is not harsh nor was there much roll with a load distributed evenly over the whole area of the load platform.
The 4.5m (14ft gin) curtainsided body manufactured by Ken Rosebury of Rochdale matched the only wheel base offered at 7.5 tonnes. We lost three retaining straps over the 210-mile route; the remainder seemed to be tight which indicates to me that someone tampered with them while the vehicle was parked up overnight.
Maximum brake stops on a wet track produced locking on all four wheels from 40mph, but with the fronts leading, the vehicle maintained a straight path. The air-over hydraulic brakes gave a progressive response, a high peak and good overall retardation under the wet conditions.
The specification of this vehicle was better suited to town-running than the rural CM route through Wales.
Summary
The lowly power output was reflected in slow journey times and a thirstier-than-average fuel consumption. In the right environment, the Bedford 7.5 tanner specified for town operation would undoubtedly show up in a better light.