Bobcat Zero-Tail Delivers

Bobcat Days continues this week in the Czech Republic, but I'm not attending this time, my understanding is that our esteemed editor Graham Black will be making the trip and he will have full coverage in the next edition of Earthmovers.

So I thought it was a good opportunity to look back at this report I did on the E55z model with my local dealers Hamblys who will also be present at the Royal Cornwall Show this week.

Always up for some time in the seat, I recently had the opportunity to get a “hands on” experience with the 5.5-tonne class Bobcat E55z mini excavator demonstration machine from Hamblys. We travelled to a secret location in the South West of England, where we were able to put the machine through its paces.

The initial Bobcat R-Series models were launched as far back as 2018 following a 5-year research and development period and made their first public appearance at the Intermat trade fair in Paris that same year.

The R-2 Series upgraded models were launched in October 2020 and longstanding readers may recall in 2021, I travelled to Kent based dealer Versatile Equipment to try out the conventional tailswing model the E60, so this was a great opportunity to try out and compare its zero-tail sister the E55z.

The E55z R2 is regarded as the Premium Zero House Swing (ZHS) model in this weight class weighing in at 5346 kgs, with power coming from Bobcat’s Stage V emissions compliant 3-cylinder D18 power pack, which in this application is rated at 36.4kW (49hp) slightly less power than the E60 model which utilises the D24 engine rated at 41kW (55hp) but slightly more power than the E50z which uses the same D18 engine downrated to 31.3kW (42hp).

These machines are very familiar to me personally as I have spent a lot of time with them, thanks to having a great working relationship with the Bobcat team in Dobris, Czech Republic, but as with all machines I test drive, it’s important to take an in-depth look around them first.

Starting off at the engine bay, the bonnet rises up, nicely assisted by a gas strut and locks into place to enable you to conduct the daily checks. It’s a tight package inside, but access to vital components such as the dipstick, oil filter, air filter and coolant expansion bottle is easy. I especially like the large colour coded yellow engine oil filler cap to the right-hand front of the engine, which clearly makes for easier topping up.

Both corner panel vents that are made of tough composite material, are removable for increased accessibility if required during major servicing. Nestling beneath the exhaust muffler box I spot the Bosch Rexroth hydraulic pump, the heart of the machines hydraulic system and one of many blue-chip components fitted on the E55z. Track motors on this machine are sourced from Doosan, as is the swing motor.

On the offside of the machine, the entire bonnet flips forward assisted by a gas strut to allow great access to the 15.10 litre plastic hydraulic tank, the Bosch Rexroth hydraulic valve block, associated hydraulic pipework, and the screen wash bottle. A convenient storage holder for the grease gun is also located under this panel next to a small storage tray which can be used to store such things as spare grease cartridges and the like.

The filler cap for the 72-litre fuel tank is located on the rear nearside of the machine in a recessed position, for ease of filling when topping up with a jerry can for instance.

The 2523mm long undercarriage, is exactly the same as that fitted on the conventional tail E60 model and features the standard 400mm wide rubber tracks, but steel tracks are available as an option for those who require more durability.

Five Dual flange bottom rollers are fitted as standard on the E55z, which helps to offer much more stability during over-the-side working, and also a much improved and smoother ride for the operator when tracking around on rough ground, but also less vibration when tracking on hard paved surfaces, one top carrier roller is fitted.

The machine can also be fitted with the optional Auto Track Tensioning System (ATTS), which as the name suggests, constantly monitors the track tension, and automatically adjusts to suit, resulting in less incidents of losing a track due to them not being adjusted manually to take up any slack, a great peace of mind feature, which can prevent unwanted downtime situations.

The dozer blade is 1959mm wide and I believe it features a “float” function for ease of levelling, although I never tried this out during my time operating the machine, a useful addition to have on-board though. In addition, four dedicated tying down points are also integrated into the undercarriage on the outside, and two more on the inside track frame for improved safety during transportation.

This example was fitted with the standard boom and the UK preferred long dipper stick offering, which is factory fitted with steel hydraulic quick coupler pipework. As a side, the quick coupler fitted was from Geith who are also owned by the parent company Doosan.

Auxiliary pipework comes as standard and Bobcat state that the machines can be supplied with up to five independent auxiliary hydraulic circuits and can offer in excess of 80.50-litres of auxiliary oil flow per minute, for running those oil hungry attachments.

Opening up the cab door, it was good to note that when locked in its open position, it remains well protected within the confines of the revolving upper-structure. Climbing up into the cab, and it’s all very familiar. The cab itself is made by Fritzmeier the German specialists who seem to manufacture cabs for a wide range of OEMs around the world. Its slightly smaller inside compared to the E60 model according to the spec sheet, but it’s hardly noticeable when sat inside it.

I especially like the big composite anti slip step that has become a familiar feature on these Bobcats, and the uncluttered floor space is a welcome addition. The foldaway track pedals are a nice touch, but could do with being slightly larger, I’m only a size 7 boot, but even those seemed too big for the pedals.

The cab interior is as we have come to expect from the Bobcat product, nicely laid out and well finished in black and grey plastic trim, and most of the controls, buttons and switches are located to the operator’s right-hand side, there is plenty of room inside, but as reported previously no room behind the seat for an operator’s lunch bag/box.

This model features the standard 5-inch colour display monitor, which is perfectly adequate and provides all the necessary machine status information back to the operator, such as fuel level, water and oil temperatures to name a few. Heating and air conditioning is fitted and distributed via five adjustable vents around the cab. For those who prefer the fresh air, there are plenty of options, with the choice of two sliding windows on the offside, and the front top screen can be raised and stored in the roof.

The fully adjustable manual suspension seat I found to be really comfortable, with seat cushions that hold you in place very well. Having got myself comfortable it was time to put the machine to work. We were located on the site of an old moto-cross site and were invited to dig away as we saw fit on the proviso that we reinstated the ground afterwards.

The machine features keyless start, so with a quick turn of the on/off switch the machine fired up, having allowed it to warm up, I lowered to isolation lever and with a quick tug on the right-hand joystick the machine sprang to life.

Cranking up the throttle dial to the maximum setting I was somewhat surprised at how quiet the machine was, I would imagine its similar to the E60 which was rated at 77dB(A) at full chat, or possibly even quieter.

Tracking up on an earth mound that was covered in vegetation, with the early morning due, it was somewhat slippery under track, but the machine coped admirably as we powered up the slope, with the boom outstretched to keep the weight forward. 

Once on top, I started to strip the vegetation and got a feel for the machines gradeability, throwing the material behind me as I progressed, with a slew speed of 9.30rpm it’s not the fastest in that aspect, but perfectly adequate for the task in hand.

Taking a bigger bite in the ground the machine demonstrated is powerful capability even with a grading bucket on, so much so that if I forced it too, it could quite easily pull itself along on the slippery top surface.

Have dug down to a decent surface, I tracked back and deployed the dozer blade to further push out what I had excavated previously, once again the machine demonstrated excellent power in the push. In line with many other mini excavator manufacturers the dozer blade lever incorporates the two-speed tracking selection button on top of the lever, which is very useful went you want to travel back at speed before selecting the low speed for the push, as previously mentioned the machine features a dozer float function but I never deployed it on the day.

I then opted to do some trimming up of the banks, I have always enjoyed landscape finishing work. The E55z features a maximum reach at ground level with the long dipper of 6232mm and a maximum dig depth of 3834mm so from the plateau I was sitting on it was well within its working range to reach down to the original ground level. Whilst working over the side I tested out the stability of the machine with a heaped bucket at full stretch. This is often a challenge for zero or short radius style machines but the Bobcat remained fairly well planted on the spot despite my attempts to upset it!

With the boom set in the straight-ahead position you can’t actually clean right up to the blade, but with the boom offset to the left (75^o) you can pull in close to the right-hand side of the dozer blade. With the right hand offset only being (50^o) it’s not possible to reach the blade to do a dust pan and brush style clean up.

This machine certainly ticked a lot of boxes for me and for those working in tight congested sites Bobcat’s Zero House Swing design, where the upper structure remains fully within the footprint of the tracks, this provides peace of mind when working in close quarters to buildings and other structures.