27 March 1998

ZETOR

7341

farmers weekly and its Dutch

sister magazine Boerderij

join forces to evaluate

Zetors brand-spanking-

new 7341. Andrew Pearce

gives the joint verdict

BY THE time you read this, Zetors new tractors will be here. Out go the old Unified Range 1 models, in come the Unified Range 1 Supers. Engine powers stay at 60-84hp but the last model digit changes from 0 to 1.

Of course theres a little more going on than fiddling with numbers. Try for size a fresh cab and revised engines, a modified gearbox with shuttle option, and more hydraulic performance, all delivered for a cost rise of around 4%. By apparently improving the package yet still keeping price a significant notch below baseline versions from other stables, Zetor is hoping to find new customers for these straightforward tractors. Does the 7341 – at 84hp and £21,110, the turbocharged top dog – have whats needed?

First impressions suggest that it might. Lets deal with the quality issue first. If someone waved a wand and stripped the 7341 of all badging, a quick tour of the outside would suggest mainstream European origins. Fits and finishes are OK, the motor is tidy, wiring is carefully loomed away. Only the unyielding-looking Barum radials and sharp-cornered rear mudguards might make you wonder.

Poking around number 28 off the Brno production line shows a few shortfalls, like irritating hard edges on the steering wheel spokes, a springy and hard-to-close roof hatch and cheap-feeling heater controls. Otherwise, clues that this is a budget tractor are few. Most minor controls work well and the plastics look pretty modern.

At 3814kg including front weight, the 7341 is light for the class and simple with it. So it wont make too much of a dent in grassland, arable men might fancy adding wide tyres for top work, and technophobes everywhere will be completely at home with its levers. Theres not a transistor in sight.

Cab

Its really wide, this all-new Czech design, sitting like a big glasshouse on the narrow-tracked test tractor. Sadly, massive space at shoulder height is squandered lower down. At console level theres fresh air where there might be storage (a single steel toolbox is all you get) and at floor level, control levers have invaded in a big way. While leg room in front of the mechanical KAB seat is generous, the steering column really needs reach adjustment to keep tall drivers happy. Rake adjustment is promised.

A single main gearstick helps offside door access; watch your feet here as the fuel tank squeezes step width. Moderate-sized mirrors mount on the cab, need a spanner to adjust and can contact the unwary head. A monumental passenger seat is both standard fitment and high on comfort, folding upward to get in the way of hitch release operation and revealing unexpected cupholders moulded into its base.

Views are a mixed bag. Good to the front thanks to a slight curve in the redesigned bonnet and an offset exhaust, the vista recedes as eyes sweep rearwards. First things to get in the way are tall console sides, then a clumsy horizontal rear divider limits sight to the lift arms. But cab pillars are narrow and glass is generous in the doors and front lower panels, so this is not a dingy place to work.

The 7341 is worked by simple levers. Its all a bit disorganised and control marking is often poor, but in use most things make sense. Not included under that heading are the wacky engine-start procedure (pull gearstick left with right hand, reach across under the steering wheel to turn the key) and the way you kill the motor by pulling the hand throttle back to its stop. Thats convenient, but can catch you out at headlands when both hands are busy with the gearstick, linkage lifting and the pto lever. A springy, hard-work foot throttle doesnt help control.

Unusually, loader controls can find an easy way into the cab through a large grommet below the front glazing. Rear implement cables can enter though a smallish back hatch, but youll have to rig your own mountings and 12V power supply. Outside, the back lights are out of harms way high on the mudguards, and two work lights can be reached for adjustment from the drivers seat.

Ventilation is looked after by a low-puff fan and single row of head-level vents, so is not likely to blow you out of the seat or thaw those frozen toes. Side windows scoop in air, the rear screen uses a single reachable handle and offers the most convenient latch weve come across. Overhead, the roof hatch is big. Air-con is an option.

Zetor hasnt yet cracked the noise business. Silsoes electronic ear found 84dbA in the loudest gear, which tallies neatly with the makers claim. Putting the figure into power class context, its a shade louder than Masseys 390, equals Valmets 865 and is substantially noisier than John Deeres much fancier 6200. So absolute sound pressure is no big problem.

But noise quality and vibration are. In fieldwork the 7341 never manages to be less than gruff, even in its sweetest spot between 1700rpm and 1900rpm. And with floor vibration coming and going it often turns crude, with a big boom period around 1500revs and an underlying groan from the working pto. While this is all quite bearable, sophisticated its not; the factory needs to put more work into this area. Things are better on the road, where transmission and axle noise are very low – even with the back window open – and the motors gurglings level out.

Engine

A 3922cc turbocharged four is carried over from the 7340, albeit with redesigned manifolds and lower emissions. With only 20 hours on its clock, the test unit showed an under-par 71.7hp maximum at the pto (75-76hp would be more like it) and 202lbf ft max torque at 1501rpm. The importer says both figures would climb as the motor bedded in.

Theres no constant power band and no overpower, although output only drifts down by 1.6hp in the first 200rpm fall. From there it declines gently with revs. Meanwhile torque is building gradually to a 1501rpm peak, showing a modest 18.1% rise in the process. Fuel consumption at maximum power is 257g kW/hour, so the Zetor is an average drinker at this point. Starting with a full 120-litre (26gal) tank, the 7341 could work flat out for just over seven hours.

To play with in the field we gave it a two-leg subsoiler working 700mm (27in) deep, then a 3m (9.8ft) rotavator digging at 100mm (4in). The motor – one of the bigger capacity lumps in the class – shows a generous heart despite its average dyno showing, settling down for a scrap as load pulls speed back from 2200 rated rpm.

Useable mid-range reserves open the possibility of easy-on-the-ears draft work around 1800revs, and the motor feels pretty stubborn on long road hills. But once turbo help exits at around 1400revs, output falls fast.

Transmission

Its just as well that the 7341s motor tries hard, as there are not many gears to help. A five-speed box plus high/low ranges give 10×2 ratios, which on the "high speed" version tested spread up to 24mph (38kph).

The box offers synchro on all but first/reverse and the option of a separate, non-synchro mechanical shuttle. Gear pattern in the three-up, three-down gate has changed, with first up and opposite reverse and even-number gears along the bottom. Presumably early mornings in the Czech Republic are alive with crunches as Zetor drivers forget the dog-leg between first and second; Silsoe certainly was.

Few gears and a wide speed range makes big steps inevitable. The Zetor has five ratios in the 2.5-7.5mph (4.0-12kph) fieldwork zone, spanning two ranges. The smallest available speed jump is 29.9% between 2nd and 3rd, with others at 40% (1st to 2nd), 60% (3rd to 4th) and 58% (4th to 5th).

Given that current thinking aims for 25% maximum between ratios, the 7341s cogs really are light years apart. In the circumstances the compromise is not a bad one. But on pto work the driver will often not be able to maximise output; and with draft operations may find one gear too high for engine comfort, then the next too low for maximum forward travel. On top of this, moving between 4th low (3.7mph/6kph at rated speed) to the closest step (2nd high and 5mph/8kph) takes a range shift, and when working in low box the maximum reversing speed (1.7mph/2.8kph) is painfully slow.

Better news is that transport ratios dip well under 6.2mph (10kph), so a load can be moved off without heavy clutch slip or negotiating a range change. And the engines flexibility lets the driver hang on to a cog in jobs where engine speed is not critical.

Good lever operation would make life easier. Here the revised gearbox is another mixed bag; main shift throws are short but its best not to fight the box or it fights back. Particularly 3rd, which is easiest entered on the move by double declutching, and can be very elusive at a standstill.

Range changes come from a short stick below the seat. Unsynchronised, these are easier than lever size suggests but call for monkey-length arms.

Directing the drive is a good clutch. Its not light, but take-up is completely progressive.

Overall the 7341s gearbox is limited in options, particularly alongside the competition. A simple two-speed splitter would even up the odds, while the Unified Range 3s triple-step powershift would be even better.

PTO

Zetor offers the driver 540 and 1000 shaft speeds from a six-spline stub, with speed selection on another low-set stubby lever. Alongside, an unmarked sibling selects between engine drive, neutral and groundspeed drive. Speed selection and drive take-up are no problem, and there is reasonable attachment room round the fixed shaft guard.

Power take off clutch engagement is mechanical with air servo help. Should the on-board air supply pack up, a heave on the long engagement lever still does the job. Thats useful – but as an electrical switch under the lever is all that triggers servo engagement, why not move this up on the dash to make operation even easier?

Power take off speeds fall at 1994rpm (540) and at 2050rpm (1000). Dyno results show power gently dipping and torque climbing gradually around here, so the motor probably wont be able to really nail pto speed through heavy load fluctuations.

We also wonder whether an Economy option alongside 540 might be a better bet for top work-inclined users. As things stand, the motor hasnt the reserves to hold the 1000rpm gear steady at low engine speed.

Rear linkage

All is simplicity round the back. An easy top link, turnbuckle adjustment for the right lift arm, pin-and-hole stabilisers giving three positions plus float but no tightening option. A double-ended drawbar delivers clevis and hook options, with swaps a two-pin business. Unsurprisingly, the hook cant be seen from the drivers seat when down.

With a full set of front weights and a heavy two-leg subsoiler or a 3m (9.8ft) rotavator on the back, the 7341 feels well-balanced. Two assister rams help the linkage to a startling 4967kg maximum lift. Trouble is, thats at the OECD starting position with link ends 200mm (7.9in) off the ground. From here effort drops to 4121kg as the arms reach horizontal, then fades to 3764kg by the top of a generous 700mm (27.6in) arc. So rather than rising to balance an increasing need, capacity falls – but it still blows away most of the class competition.

Draft control is top-link sensed. Position, draft and preset mix come from a sub-lever alongside the main quadrant, and on the floor nearby an unmarked handle varies response rate. Between them, these allow plenty of control options and generally the draft system shows a wide sensitivity range.

A couple of points turned up. Lightly loaded, Zetors all-hydraulic system responds only in coarse steps to quadrant lever movement, which can be a pain when hitching on. With load on the arms things improve, though in draft work a stepped response is still noticeable. Using a lower top link hole at the tractor might have helped, or maybe weve got too used to the precision of electronic systems.

Hydraulic services

An easy-to-get-at gear pump on the engine block supplies open centre hydraulics. Standard fit for the 7341 is a single double-acting spool, with up to three more optional. Hydraulic couplers are set high and well apart for easy access, and theres a free flow return. Zetor says oil output has been increased for the 7341, and test results put it smack on the class average for hydraulic power with 14.4kW at 180 bar. Maximum flow is 55.6 litres/min, maximum pressure 207 bar.

The single spool lever is easy to feather, and system output sends a twin-ram loaded trailer skywards at a good rate without screaming the motor.

Four-wheel drive

and diff locks

Air pressure holds open the driveline clutch, so the system can revert to engagement in case of failure. No-problem operation comes from a low dashboard switch, whose own lamp could usefully be backed by a second dash panel warning light.

The front axle holds a limited-slip diff which looks after itself. The rear axles 100% lock is put in by air pressure and should be released by a push on either independent brake; in practice it often took multiple shoves before the lock popped out. This only adds to the notion that the system needs a bigger warning light on the dash, right under the drivers nose.

Steering, brakes

and roadwork

New for high-speed 7341s is a Carraro front axle. Though not a 55í unit, it still delivers tight turns. The test tractors small 9.4m (30.8ft) circle in two-wheel drive comes from 3.25 turns of the wheel, with effort increasing at tick-over – and there looked to be more to come from the lock stops. A leak from the steering box showed during testing, which turned out to be a loose union.

All four brakes are now wet units, with a linked trailer line an option. System performance is fine, anchoring the tractor and an unbraked trailer with no trouble. Independent braking is achieved hydraulically, with the master cylinder sensing whats going on and stopping only a rear wheel during fieldwork turns.

Maintenance

Screw-in dipsticks serve the engine and back axle. Most daily checks dont involve disturbing the lift-off side panels, though looking at coolant level does. Filters are all out in easy reach, the air cleaner and battery are simple to access, and the radiator – though fixed – sits alone and has good protective screens to the sides and underneath.

&#8226

Driver sits well up in new Zetor cab, with good leg-room. Column extension would help tall men. Folded passenger seat (right) is comfortable but massive.

Red-topped main gearstick is just where you need it. The same cant be said for the non-synchro range change – its a reach down and not easy to use in a hurry.

Nothing electronic here. Quadrant lever looks after linkage, backed by position/draft selector (bottom) and stepless response rate lever out of sight below seat. Single spool control is standard; outlet delivers good flow for class.

Wide, uncluttered dash blocks some sight of the front wheels. Dials and controls all OK, except hand throttles engine stop function and lack of back-up dash lights for 4WD/diff lock.

Mini forest of levers under the operators right hand look after the parking brake (red) pto (yellow) and at the back, the hitch release. Handbrake is just where you need it. Hitch release isnt. Controls below are for the pto.

LIKES AND DISLIKES

We like

&#8226 Good balance.

&#8226 Engine willingness.

&#8226 Draft options.

&#8226 Clutch.

&#8226 Four-wheel braking.

&#8226 Simple linkage.

&#8226 Hydraulic performance.

We dislike

&#8226 Cab noise.

&#8226 Limited gear options.

&#8226 Gearshift.

&#8226 Limited rear visibility.

&#8226 Oversize passenger seat.

&#8226 Limited ventilation capacity.

&#8226 Foot throttle.

Elementary 7341 linkage has two assister rams and big capacity. Arm ball ends are standard, top link and stabilisers are easy to get along with. Rear lights are safely high on the mudguards.

Springy foot throttle offers little precision in operation. Domed head on independent brake latch beyond allows foot operation; lower section of vertical cab trim beyond that has no scuff protector

where it meets the floor.

Double-ended drawbar is quick to switch round, at least before meeting mud. Hitch hook is invisible from the seat – whats new.

About the test

Silsoe Research Institute measured the Zetors capability in engine performance, fuel consumption, lift capacity, etc to OECD standards. Then, without seeing the results, we used the tractor over two days with a two-leg subsoiler, 3m rotavator and 8.7t tandem axle trailer.