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Tractor test: Case IH Puma CVX 230

Editor’s note: We’ll be including some of Profi’s field tests reports on new machinery in the next few issues. Some of the features on the European models tested are a little different than those on North American versions, but you’ll still get a good feel for these machine. For more information on Profi magazine, visit www.profi.com.

Puma’s horsepower

At the end of 2010, Case IH started the roll-out of its new Stage IIIB/Interim Tier 4 tractor line-up and was particularly vocal regarding claims for significantly improved fuel economy and performance. Not that the previous model was all that bad. In fact, when we assessed the Stage IIIA semi-powershift Puma 180 in the December 2008 issue of Profi, its Powermix fuel consumption result of 287 grams per kilowatt hour put it in a strong position and set the benchmark high for the Stage IIIB-compliant Puma CVX 230 tested here.

With this in mind it will be a comfort to past and potential Puma buyers to learn that both tractors share many features and components, including their 6.7-litre Fiat Powertrain Technologies engines, albeit the newer model benefiting from an SCR catalyst to take care of exhaust emission clean-up.

More importantly for buyers, though, is whether the latest Puma’s performance bite remains as powerful as its trademark and distinctive bark. To find out we handed our Puma CVX 230 over to the DLG (German Agricultural Society) testers. According to the brochure, this Stage IIIB motor should be knocking out 228 horse power. As it turned out, at rated speed only 197hp arrived at the PTO, and similarly only 27 hp of the claimed 34 hp boost power made it from the engine to the tail end. Note that boost kicks in when ground speed exceeds 0.5 km/hr with the power take-off engaged, or when travelling over 15 kilometres per hour on transport duties.

Despite these efficiency shortcomings our test tractor delivered a useful 21 hp of extra power, which brought the maximum PTO output to 240 hp — all good stuff. The tractor’s power boost curve also shows an impressive torque rise of 43 per cent, ultimately securing the tractor a “good” mark for its overall engine performance.

Fuel economy

On the subject of fuel economy the Puma guzzled 240 g/kWh at rated speed and as little as 223 g/kWh at max output, placing it among the more economical tractors we’ve tested. Indeed this return is six per cent lower than the tested competition, including the Puma 180 previously mentioned.

But before we get carried away, it’s clearly important to take into account the amount of diesel exhaust fluid (DEF) our test Puma consumed. This rate is 20 g/kWh and nudges the combined economy back to mid-consumption levels for this power bracket.

The reality is that, in terms of our power-mix tests, the Puma CVX ranked as one of the best tractors we’ve ever tested and reinforces a trend we’re starting to witness with these latest Stage IIIB tractors. It posted a result of 263 g/kWh or 12 per cent below average and even when adding the DEF rate of just under six per cent, fuel operating costs should be low for the hp.

Holding 48 litres, the DEF tank should have sufficient capacity for two fills of the 395-litre diesel tank. When the DEF level is down to five litres, the operator sees a yellow warning light, which turns red once capacity is down to two litres. At this stage the engine starts restricting its output by five per cent every two minutes until it reaches 50 per cent. If the user continues to drive with the DEF tank empty, the engine shuts off. The operator gets a second chance to restart the engine for 30 seconds to extricate himself from an awkward situation — sitting on a railway crossing, for example — but then the tractor will shut down again.

Back to more normal circumstances, when the engine is turned off the SCR system withdraws all liquid from its lines, as DEF freezes at -11 C. Similarly, when the operator first fires up the engine in freezing temperatures, it runs for up to 30 minutes without using DEF. The intervening period allows a heater to warm the DEF tank with heat from the engine coolant.

Double-clutch system

On down the driveline we find the infinitely variable speed transmission produced at CNH’s Antwerp factory. This gearbox has four mechanical ratios when going forward and two for reverse. The modern double-clutch system makes the automatic gear changes so smooth that the operator hardly feels them.

Automatic Power Management, or APM, is the engine-transmission management system that allows the operator to use the split throttle controls on the multi-function armrest. Simply set the minimum engine speed with the left control and the maximum speed on the right. Programming the PTO speed is vice versa: the left control sets the target engine speed and the right split adjusts the amount the engine can die back before the ground speed is altered.

There is the option of storing three transmission speed ranges and freely swapping between them. The speed range can be tweaked via the dial on the Multicontroller. If the Puma’s operator rises from the seat, the tractor auto-applies the parking brake. Indeed, the Puma’s handbrake lever is only present to comply with legislation and, proving the point, we never used it.

Top marks go to the four PTO speed options, giving the Puma an advantage over some of its CVT competitors, and these PTO speed changes are implemented via a dial in the cab, which governs a motor on the speed selector. Those operators who prefer not to utilise a tractor’s headland management system — the Puma’s only allows recording on the move — will welcome the fact that they can still independently activate the auto-PTO system that links PTO operation to linkage position.

Lift capacity

Now we’re at the rear of the tractor, where continuous lift capacity was tested at 7.2 tonnes. This relatively modest figure could prove problematic when trying to hoist a heavy cultivator to the top of the linkage arc, although, to be fair, any potential issue was quickly overcome in our test by moving the link arms back one hole, giving access to a further 1.4 tonnes of lift muscle.

The depth control migrates on to the latest-generation armrest, but sadly this move in location has been accompanied by the control losing its base ring stop. Other niggles include Case not offering a true electronic linkage control intermix function and persisting with CBM quick couplers that are reluctant to lock properly. On the plus side it’s now far easier to change the stabilisers’ position.

Glance up from the stabilisers, and you’ll spot up to five rear spools, which can be joined by up to four mid-mount valves. Naturally, this multitude of spools requires a similar and bewildering number of control options in the Puma’s cab — either on the Multicontroller, a double-function cross controller or on four rocker switches. At least, though, there’s no need to activate the linkage and hydraulic systems after starting the engine, a requirement that often leads to novice operators looking befuddled and having to call for help.

Owners of the previous generation CVX will have to get used to the idea of the back-end oil being shared between the transmission and hydraulics. Not that this is a particular problem; for the Puma, it’s just different. Oil is supplied by a 150 litre/min. or 170 l/min. swash plate pump. Our test tractor had the smaller version, which delivered 130.7 l/min. and 34.5 kW at the rear spools — hardly record breaking outputs so, where this is likely to be a concern, we’d recommend investing in the larger 170-litre unit. The rear spool valves do not couple under pressure and also have separate leaked oil containers.

In the cab

Maintaining this upbeat theme, there’s much to like about the Puma cab. The mechanical suspension is more stable than before and, though not quite as subdued as the 69dB(A) brochure claim, our test tractor still managed a pleasing 72.7dB(A) result. Our only cab grumble of note is with the ease of identification of some of the controls: flexible keys within the armrest are difficult to distinguish; and the same applies to some of the buttons on the Multicontroller joystick, which are arranged disconcertingly close together.

Addressing this criticism, at least in part, Case IH confirms that the armrest panel and Multicontroller will benefit from backlighting on 2012-production tractors. With its seven-inch touch screen, the AFS300 terminal provides multiple customised screens — a level of choice that can, at times, lead to confusion, although, to be fair, operators are able to program the spools without having to wade through sub-menus. If you’re planning on connecting ISObus implements, our advice would be to go for the AFS700 12-inch display.

Summary: Experience gained over the past few months means that we’ve now come to expect Stage IIIB/ tractors to score top test marks on fuel consumption, and Case IH’s Puma CVX 230 certainly doesn’t buck the trend. In many ways the tractor builds on the strong foundations laid by the Stage IIIA Puma, though we still wouldn’t go quite as far as to say there’s no room for improvement. Perfect? Of course not. Commendable and attractive overall 200-250 hp package? Absolutely. †

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