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This tractor took part in both the 2003 and the 2006 Guinness World Records for the most tractors working in one field at the same time, driven by Carl Newton. 2,141 tractor in fact - a new world record. History: Original material by Keith McRone and printed in the Stationary Engine magazine issues 92 and 93, Oct. and Nov. 1981. (reprinted here by kind permission of Kelsey Publishing). |
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The Lister ‘Goldstar’ Tractor by Keith McRone A Lister interest in agricultural automotive applications dates back at least 60 years to the period immediately following World War 1 when the company manufactured the novel Wyles Motorised Plough. Later in the mid 1930’s, CE twin cylinder engines were supplied to Brinkman & Niemeyer N.V in Holland to power their 16h.p. agricultural tractors -- one of the first pure Diesel tractors to be marketed. Other projects have involved the design of the SL4 engine for powering a small Allis Chalmers tractor, and the adaptation of the HA3 engine for Renault application, but the most ambitious venture undertaken to date has been the construction of a simple agricultural tractor designed to meet the needs of emergent countries, with North Africa, Iran, and China particularly in mind. The name GOLDSTAR was adopted as a compliment to the flag of mainland China. The original concept was to produce a unit which was essentially an air cooled engine on wheels with a hook behind which would functionally replace a pair of oxen. The power unit was to use to the maximum extent standard industrial engine components already available world-wide through established Lister outlets, the tractor was to be completely non-electric so that it could be readily started, operated and maintained by people having only a rudimentary engineering ability, and as a matter of principle it was decided that the Company would not become involved with the specialist engineering of transmission design, but would use a proprietary rear axle assembly of proven reliability. The unit eventually built was a combination of HB2 engine with rear axle of ZF manufacture, giving six forward speeds, one reverse, and a maximum drawbar pull of about 2.75 tonnes. Later developments allowed the engine speed to be increased from 2000 to 2200 rev/min, corresponding to a road speed of 25Km/h (16mph) with 10-28 tyres. The ZF rear axle incorporated individual inboard brakes, foot operated differential lock and a conventional power take-off shaft at 540 rev/min. With hindsight it may have been unfortunate that these refinements were available as part of the standard ZF unit, as it encouraged an over easy departure from the root concept of a simple ‘engine on wheels’ and eventually resulted in an over-sophisticated specification becoming available at an uncompetitive price. Fig 4 shows the air inlet housing bolted to the flywheel end of the standard HB2 engine, giving a high level of entry for clean engine cooling air and also providing a face for mounting direct to the rear axle casing. The air inlet housing also accommodated a widely available 9” Borg and Beck diaphragm clutch. The simplicity of air cooling was seen to be a significant advantage compared with the water cooling of conventional tractors, particularly since the air cooling system was originally designed to allow for the dusty conditions and low standard of cleanliness frequently experienced in agricultural environments. At the forward end, the engine standard gearcase cover was modified to carry a deep malleable iron casting which provided a strong, rigid support for the front axle pivot and assembly. The engine was thus slung between two end face mountings, leaving the flat base of the engine crankcase free for the mounting of implements. This arrangement gave a very satisfactory high ground clearance and a clean underside to the tractor. The front of the Goldstar was completed by a tough moulded glass fibre bonnet secured by rubber toggles. The absence of a radiator gave a low profile which gave excellent visibility. The front wheel track was adjustable in 4” steps between 44” and 64”, the rear wheel track could be adjusted in 4” steps between 40” and 68”. The narrowest configuration was intended for close crop cultivation such as vineyards. Multiple front and rear wheel weights could be fitted in addition to wheel water ballasting. The decision to offer the tractor with a relatively large bore hand-started diesel engine immediately raised an important issue; the high inertia flywheels of industrial hand started diesels would give a speed of response too sluggish for automotive applications, but a lively engine could be one-man hand started. Could an acceptable compromise be reached? The answer to this problem was to make the operation of the decompressor trip fully automatic, so that the operator could keep both hands on the starting handle and so maintain maximum starting effort at the moment when the engine tripped onto full compression. This allowed the flywheel inertia to be reduced to a level which gave a modest speed of response, recognised more as a slogging ability rather than sluggishness For heavy duty operations such as ploughing and rotorvating, the heavy flywheel gave a particularly impressive performance quite distinct from the more familiar ‘automotive’ response. Apart from the technical objections to electric starting for low technology markets, there was also the proven problem of batteries being stolen making the tractor useless. Hand starting would overcome the battery problem, but starting handles seemed to also have a desire to wander, so a captive foldaway arrangement was fitted as standard. One other potential problem for non-technical drivers was what to do if the engine ran out of fuel -- as was bound to happen. Bleeding a fuel system under primitive conditions could only invite trouble, so the engine was fitted with a fuel lift pump and a fully automatic self-bleed system which required only cranking for the pumps and injectors to become properly primed. A large capacity air cleaner was provided and again the probable field conditions suggested that renewable elements would either not be available or would not be fitted. An oil bath type cleaner was therefore specified making fuel oil in the tank, lubricating oil in the sump, and lubricating oil in the filter the only functional items requiring regular attention. The engine itself could be expected to operate for 1,000 hours without attention to the injection equipment. This then was a tractor which fulfilled most of the original concept of reliable, rugged simplicity, giving a highly satisfactory performance for al manner of duties, up to 3 - furrow ploughing, which rivalled the Ferguson 35 and Ford Dexta, both of which were universally popular at the time. However, market reaction quickly showed that unsophisticated farming communities did not necessarily welcome unsophisticated equipment and a further development phase was therefore undertaken to provide additional features. Immediately, the attractive basic cost was jeopardised, as the ‘simple’ accessories involved complications which could not be avoided, particularly when considering the widely differing legislation and custom which applied in different overseas territories. For example, paraffin lamps were not considered acceptable for lighting, so electric lighting had to be specified, but this simple item then demanded a battery, control equipment, dynamo, dynamo mounting brackets and vee belt pulley drive from a modified engine. Similarly a mudguard had not only to protect -- it had to accommodate wiring, lighting and reflectors, and it had to be wide enough and strong enough to be used for passenger seating. Eventually, accessory equipment was developed which allowed the Goldstar to match the Ferguson 35 and Ford Dexta in everything but price, and simply because sophistication was seen to be on offer as an extra, the original simplicity was either unrecognised or ignored. An initial pilot production batch of 25 tractors was built for Iran -- but specification included a full hydraulics system for mounted implements, electric starting an lighting. Not surprisingly, volume business did not mature. The message was straightforward -- keep it simple, the only problem-- how to convince the customer that simple is beautiful. |
