Leyland Redline TB 750
Page 64
Page 65
If you've noticed an error in this article please click here to report it so we can fix it.
now tomgvw four-wheeler by Trevor Longcroft THE Redline Terrier series of' four medium-weight chassis for operation at gross weights of 6.5, 7.5, 8.5 and 9.5 tons is now fitted with the new Leyland 98 series engine and the improved design cab common to the heavier Chieftain, Clydesdale and Reiver chassis.
The series 98 engine — described elsewhere in this supplement — is available in fourand six-cylinder configurations for vehicle application, the six-cylinder version in two ratings, the lower of which was fitted to the 750 Terrier we have just tested.
Cab comfort The exterior cab profile differs slightly from the previous model, while the most noticeable frontal differences are a lower cooling grille and a full-width upper grille which can be removed to expose electrical equipment and the engine front.
Cab entry is easy, helped by a step about half-way between the ground and cab floor; there is also a large grab handle.
Once inside, the cab is both spacious and uncluttered. The driving seat is adjustable vertically and fore and aft and the squab rake angle may be selected by the driver. Driver and passenger seats are covered in "breathable" pvc, and this minimizes discomfort on a hot sticky day.
A notable improvement is the repositioning of the instruments from the cab centre to directly ahead of the steering wheel. The speedometer, coolant temperature, oil pressure, fuel and battery gauges together with brake pressure warning lights and direction indicator flashers are now in front of the driver. Direction indicators and vehicles lights are controlled from stalks projecting on each side of the steering column. A console mounted at head-rail level to the offside contains the windscreen wiper switch, heater blower switch and brake adjustment warning light. The ignition switch and manually pumped windscreen washer control are positioned to the offside of the steering column at knee height.
The simple parking brake control of the previous cab is retained at the right side of the driving seat.
All-round visibility is good, although an increase of head-rail height would, I feel, benefit the forward view since with the sun visor lowered an important part of the screen is obstructed.
The mirrors give good uninterrupted rearward vision and remained vibration-free even with the engine idling and the vehicle stationary.
Ride and handling Previous tests of the 650 and 850 Terriers indicated a high standard of ride and a low noise level. The 750 proved no different in these respects; driven over all types of road surface likely to be met during normal operation the cab remained vibration-free, and the only adverse comment that can be made was that a slight cab nodding was experienced, for a short period only, when travelling over a recently tarmacked road.
The main criticism of the vehicle is its heavy steering — a factor on which we have commented on' each of the Terriers tested so far. Steering effort was excessive, especially when manoeuvring and on a hot day with hands damp from perspiration, a tight grip of the wheel rim was necessary to prevent it slipping when turning. Effort decreased as speed increased, allowing overtaking at speed to be completed safely.
Five turns are required from lock to lock to give a swept circle of 53ft — an increase of approximately 4ft on the similarwheelbase Terrier 650 fitted with the original shorter cab.
Gearchanging was effortless and precise, the cranked lever came easily to hand and each gear could be selected without the driver having to move in his seat.
The ratios of the newly specified Turner gearbox — 921b lighter than the previous box — fitted to all but the heaviest model are evenly spaced and did 'not produce any flat spots in the lower rev range directly after an up-change.
Acceleration and braking All tests were completed with the vehicle loaded to its maximum 7.5 tons grosS. Stopping distances from 20 mph and 30 mph were 29.6ft and 56.7ft respectively, disappointing figures compared with the 21.3ft and 44.1ft obtained with the heavier 850 tested by CM, though the peak decelerations were very high — 95 per cent. Braking Was completed on a dry road and the rear wheels locked consistently, causing the rear of the vehicle to slew slightly to the nearside. One stop from 30 mph gave the impression that the rear axle had lifted from the ground during the stop, and inspection of the tyre marks endorsed this suspicion.
The vehicle specification included the derated 98 series engine producing 91 bhp net at 2600 rpm., the overdrive Turner gearbox and a 4.7 to I. rear axle ratio the highest ratio from the three options available.
Accelerating from rest, the vehicle reached 40 mph after 28.5sec and 40 mph after 50sec. A lower rear axle ratio would have made some improvement to the times at the expense of top speed, which was 56 mph for the test vehicle.
First gear was required only for hill starts, second gear coping adequately with flat road standing starts. Restarts were possible facing up and down a 1 in 6 gradient.
Fuel consumption Running fully laden over typical roads the vehicle returned a very creditable fuel consumption of 19.6 mpg. This figure dropped to 15.2 mpg when operating at high speeds on a motorway. A one-stop-per-mile test returned a consump• tion of 19.1 mpg. All the figures obtained were above average and were better than those obtained for similar checks on the Terrier 650 and 850.
This consumption can be attributed partly to the machine's ability to cruise at reasonable speeds in overdrive gear, the engine running at part-load.
Maintenance The cab can be tilted, but there is no torsion bar assistance and the service manual recommends that a lift be used. For routine maintenance it is not considered necessary to tilt the cab. The passenger seat is hinged and can be lifted to expose a large inspection cover easily removed by releasing four tag-type fasteners. This gives access to the top of the engine. A further panel that projects forward of the seat line may also be removed by unfastening some set-screws.
Summary The 750 Terrier, apart from its heavy steering, is a nice vehicle to drive. The cab is quiet and comfortable and the repositioning of the instruments a real improvement. Taxation weight is 2.9 tons and it is possible with a light body to keep the unladen vehicle weight below 3 tons.
In general the performance figures are average for the class rather than startling, and with this low-rated version of the engine the 750 model might be considered a little low on power, but on the other hand the fuel consumption results which it produces are excellent.
As tested the Terrier 750 costs £1856 with six-cylinder engine and five-speed vearbox. The drop side body made by J. and A. Smith. of Whitburn, costs £181 extra.