Easy access? IRN looks at the serviceability of the latest generation of mini excavators.
By Murray Pollok28 September 2010
Alongside reliability, serviceability is a key requirement for any equipment in rental fleets. This applies in particular to ‘bread and butter' items such as mini excavators. So what are manufacturers doing to make their latest machines easy to maintain? IRN reports.
If there is an onus on all manufacturers to make their products easy to service, then that is true even more so for companies who are making an effort to sell their machines to the rental sector for the first time.
That's the case for LiuGong, the Chinese manufacturer that is now establishing sales networks in North America, Western Europe and the rest of the World. David Beatenbough, the highly experienced US construction equipment executive who has been brought in by the Chinese company to head up its research and development activities - among other things - is well aware of the particular needs of rental companies.
Talking about the development of the company's latest machines, the 4 t and 6 t 904CIII and 906CIII, he tells IRN; "We started out with the goal of making service easy. The main valve is very important - you really want to be able to see that valve. We've taken it out of the body and put it up next to the access cover next to the cab." Service points in general are easy to access at the rear of the machine, such as for checking coolant and air filters.
Another feature of the new machines is a second water/fuel separator to protect the engine if poor quality fuel is used - a distinct possibility with rental machines. There are other smaller issues that he highlights, such as having a cab that is easy to sweep out, with no door lip.
Mr Beatenbough makes the point that damage prevention is another key aspect in making machines easy to own. For example, the fuel cap is recessed; door hinges are oversized for durability; and he says that LiuGong uses top quality hoses and components.
The 904 and 906 models - which will be launched at Bauma - also differ from their predecessors in being more efficient to operate, in part because of a switch from a three-pump to a four-pump hydraulic. Mr Beatenbough says this has other advantages; "it also makes it easier for inexperienced operators. The machine has multiple function capability."
Thinking about the needs of inexperienced operators comes naturally to a Chinese company like LiuGong since so many of its domestic customers are first-time users. It's also thinking that fits well with the needs of rental buyers.
LiuGong is also giving more thought to total lifetime costs; "Lifetime costs was one of the biggest considerations", he says, "We're moving away from acquisition cost. To optimise lifetime costs you have to start at the design phase. We're much more interested in the durability of components than we were five years ago."
LiuGong's excavator range currently stops at 4 t, so it doesn't yet have any of the true minis that are so popular in the rental market. Mr Beatenbough says they do have development projects for those but it will be two years before they are available. More important than rushing to expand the range, he says, is ensuring that the current products are supported in the field wherever they are sold.
Japan's Takeuchi, being anything but a newcomer to the rental market, has less to prove than a company like LiuGong. In any case, its machines have a reputation for reliability and ease of service.
Kevin McLaren, Takeuchi UK's service manager, says the tilt up cab on all its 2.4 t to 5 t models is one of the best service features of the machines, giving easy access to critical service areas. (It takes two to three minutes to unlock the cab at the turntable.)
This feature was retained in the launch last year of the new 3 to 5 t models, the TB228, TB235 and TB250. However, the company has also made some improvements; "Takeuchi's new models also feature improved ground level access for certain service jobs", says Mr McLaren, "Both for on and off site maintenance ground level access by service engineers is preferred. Takeuchi introduced separate service doors right around the machine to allow for easier access."
"Takeuchi put a strong emphasis on service for any hire fleet and have designed in features to make servicing easier and to help maintain general wear and tear", says Mr McLaren, "Takeuchi have maintained durable design with 100% steel panels and have avoided the trend of plastic panelling. The new models now feature new styled sectioned panels around the turntable and engine hood, these separate sections can be easily repaired and replaced if damaged, scratched or dinted when out on hire".
Better visibility in the cab also reduces the risk of damage to the machine. "Operators have the advantage of improved 360° visibility with three well positioned cab mirrors one internal and two external. A one piece extra toughened glass door right down to the foot well again improves visibility", says Mr McLaren.
Volvo Construction Equipment who has given serviceability a lot of thought in designing its new C-series in the 1.5 to 2.0 t class (the EC15C and EC20C are getting updates and the EC17C and EC18C are completely new, to be launched at Bauma.)
"These are completely new machines," says Jean Wilfrid Goncalves, global product marketing specialist for compact excavators at Volvo. "They offer significant improvements in performance, operator control, comfort and ease of maintenance."
Volvo says all service points are reachable under the engine hood, such as fuel and hydraulic level and filling, engine oil, air filter and coolant level checks, with all greasing points grouped on the left side of the machine. Access to the main hydraulic components is via a panel in the cab floor, and the main control valve can be reached by a similar panel with only five bolts.
The machines are also designed to better withstand wear and tear, with cast iron used for both the boom end arm base. "Hydraulic hoses are fully protected through routing in the boom", says Volvo, "Rear counterweights are made of one single piece of cast iron, offering protection from potential damage, and the front, back, side and door windows are made of SEKURIT glass, which is quick, cheap and easy to replace."
Hitachi is in the middle of a significant renewal/updating of its mini excavator range - the latest fruits of which will also be seen at Bauma. Joep van den Maagdenberg, product sales manager compact line (EAME) tells IRN that, like Takeuchi, Hitachi is retaining the tiltable cabs that were on the previous generation of machines.
Changes to the new models that will make servicing and maintenance easier include the use of improved hydraulic oil filters and engine oil filters, which will extend their service lives. The use of ‘self-lubricating' HN bushes and pins reduces service requirements, with a 500 hour interval for greasing.
The new models include the standard ZX18-3 and ZX27-3, and the short-tail swing ZX29U-3, ZX33U-3, ZX38U-3, ZX48U-3 and ZX52U-3.
Total cost of ownership is also mentioned by Mr van den Maagdenberg, who says the company's Eco Zone feature - which optimises control of engine speed and torque as well as hydraulic pressure - improves fuel economy.
At Bobcat, meanwhile, the new E08 to E16 mini excavators incorporate many features aimed at simplifying maintenance. Bobcat says features include: optimal access to routine service points and side cover openings; easy (visual) displays to check fill levels; extended engine oil change intervals (500 hours); wear bushings on critical pin joints; easy to access grease nipples; water and dust sealed electrical components; and industry common hose fittings for easy replacement.
The company adds that damage prevention is aided by designs "to provide natural protection of exposed areas - cylinder over boom, hoses routed through the boom, cast counterweight corners on the E08/E10 models, large thick wall tailgates and blade cylinder guards."
For the new E32 and E35 mini-excavators, meanwhile, Bobcat says the wide opening tailgate and sidegate offer good access for routine maintenance. Additionally, "The air conditioning condenser and hydraulic cooler can be easily separated for cleaning purposes, without need for tools. The starter, alternator and compressor can be taken out without removing the counterweight." The counterweight, tailgate and sidegate can be removed easily for unlimited access.
At Bauma, JCB will show its new 8085 ZTS, offering 13% more torque than its predecessor, the 8080 ZTS, and at lower engine speeds, thus saving up to 2 l of fuel per hour. On the servicing side, JCB has relocated the hydraulic block into the side compartment alongside the engine. "This", says the company, "results in shorter hose runs from the valve block to the dig end, reducing the number of hoses running under the cab floor. An access panel in the side of the cab ensures that technicians can get to hoses on both sides of the valve block."
JCB says that by moving the valve block to the engine compartment there is now more room in the rear access panel for remote service points and the cooling pack.
In addition, the fan and air conditioning belts have been relocated for improved access, and all check and fill points are positioned for easy reach from ground level.
JCB says the main service intervals remain at 500 and 1000 hours.
In terms of damage prevention, improvements have been made to the hose routing through the king post for increased protection.
In terms of brand recognition in the rental market, JCB is light years ahead of a newcomer like LiuGong, but even it can always find ways to improve its products.
Wisconsin, US-based ExtendQuip has launched a new version of its TMX towable mini excavator. As the photo shows, the big feature of the machine is an integrated tow-bar that allows road-towing at speeds of up to 105 kph (65 mph) without the need for a transport trailer. ExtendQuip says this makes them ideal for the ‘DIY' and small contractor market.
"Unlike conventional mini-excavators", says ExtendQuip, "TMX units eliminate tracks by utilising zero-turn technology common on lawn mowers. The zero-turn rotation enables convenient access to tight locations and allows work on well-established lawns or greens by virtually eliminating the potential for turf damage. The drive tires are designed for mud terrain, ensuring performance and traction in demanding applications.
The TMX is a 1.5 t class model, with a 2.4 m digging depth, which Extend says is equivalent to a conventional 3 t mini excavator. With a 3000 kg digging force, the TMX unit offers a claimed minimum of 21% more digging force than similar sized competitive excavators.
A spokesperson for ExtendQuip says the company has a lot of interest in international markets, although no dealers or distributors yet. For more details, see www.tmx-excavator.com