Notes from the Underground

In an innovative application a Darwin plumber has set up a fully functional vacuum truck based on an Isuzu NPR Traypack.

Scott Stewart is a plumber by trade and became involved with vacuum trucks while he was working on various road tunnel projects in Sydney.

Scott’s progression to a supervisory role provided him with an insight into the costings and hire terms of specialised equipment such as truck-mounted vacuum units. Scott moved to Darwin in 2013 and again worked with vacuum trucks on numerous projects including during the construction of the massive INPEX gas facility.

After the completion of the construction phase at INPEX Scott identified an opportunity for a downsized vacuum truck which was still capable of handling the potholing excavation, drain cleaning, and CCTV camera inspections of underground pipework that conventional vacuum trucks performed and to have the benefit of being able to access spaces which may present tighter access.

“It was an idea of mine from a while back,” says Scott.

“There are a lot of big ‘vac’ trucks in the industry, and I thought I could make a small one possible to target a niche market specialising in smaller scale projects and jobs. The truck was my COVID project.”

Isuzu NPR 45-155 Premium Tradepack.

After considering several brands of new trucks, as well as second hand units and even tippers, Scott’s final analysis pointed him to the Isuzu NPR Traypack for three main reasons.

“For starters, the Isuzu Traypack comes equipped with a bullbar, ladder racks and a soap dispenser,” he says.

“The extras that it comes with make the truck look very professional for the same cost as something such as a HiLux. The ‘bang for my buck’ in terms of the Isuzu’s storage and carrying capacity was the second reason, and thirdly it was just actually driving it. I’ve driven Isuzu’s a bit in my time and I’ve always rated them as a good truck.”

Scott purchased the Isuzu NPR 45-155 Premium Tradepack through local Darwin Isuzu dealer CJD in June 2020.

His goal was to have it finished by the end of the year and, mostly working on weekends, he managed to have it ready to operate by the end of October.

Obtaining the necessary paperwork for items such as the required environmental licences takes some time to process so it was the beginning of 2021 when Scott’s business Quality Underground Excavation Service Team (QUEST) began its operations.

The Isuzu NPR Traypack is usually sold as a ‘ready to work’ vehicle and Scott accepted he would have to make some modifications and additions to suit the specialities of his intended purposes for the truck.

As a result of his research into the most suitable vehicle for his specific needs, Scott upgraded the Isuzu’s suspension by adding a couple of extra leaves to the rear springs to help when fully loaded especially in consideration of occasions when the 1,000 litre liquid spoil tank is full.

The Isuzu is also equipped with a 400 litre clean water tank. Scott credits local company A&K Maintenance and Mechanical for its assistance in making the truck an operational reality and making best use of the available tray space in order to accommodate items such as pumps and hose reels.

Scott Stewart at work near Darwin.

“I was able to work with the specifications and my mechanic at A&K and I spent the time to shuffle around the mounting locations of the various pieces of equipment I required in order to make them all fit,” he says.

“The dealer has a computer program that does all the weight distribution and when it came down to finally putting it together with the new items the accuracy was down to the millimetre. We could fit everything we wanted such as the Vermeer vacuum pump and it worked out spot on.”

A lot of Scott’s work is involved in using ultra high pressure water jets to perform non-destructive hydro-excavation including ‘pot holing’, as a method to locate underground utility service locations including water and sewerage pipes without the risk of damage that a mechanical excavator would encounter if used to perform the same job.

The Isuzu has also proved to be very effective for the cleaning and regular maintenance of large boats.

The high pressure water jets are ideal for cleaning the outside of boat hulls and the vacuum pumping function also lends itself as the ideal and safest method for the removal of the liquid waste which collects in boats’ bilges and holding tanks.

These liquids are frequently contaminated with hydrocarbons and display the consistency of oily water.

The Isuzu Traypack has a Gross Vehicle Mass of 4,500kgs allowing it to carry at least a tonne more than a conventional ute and is still able to be driven by the holder of a passenger vehicle licence.

The height dimensions allow Scott to easily access shopping centre car parks and, importantly at lunch time, McDonald’s drive-throughs. Scott is impressed with the Isuzu’s on-road performance delivered by the 155hp (114kW) four cylinder engine and the six speed automated manual transmission.

The Traypack comes with a tow bar as a part of the total package and the towing rating of 3,500kgs for a braked trailer far exceeds anything else Scott looked at when considering the candidate for his project.

The additional capacity for a trailer allows for the transport of a small excavator or an additional liquid spoil tank in the future.

“Up here in the Northern Territory the speed limit is 130km/hr on the freeway and I can easily cruise at 130 kms between jobs and with the 65 litre fuel tank I still get 500 kilometres out of a full tank even with the load on the back.”

Scott also appreciates the spacious Isuzu NPR cab which can accommodate three adults in comfort which is a significant advantage over a conventional single cab ute.

The driver and outside passenger are afforded supplementary safety due to standard airbags. The driver has a suspended seat and the coil sprung independent front suspension delivers a car-like ride for all the occupants.

Scott Stewart inspects the 100 litre spoil tank.

Isuzu’s electronic stability control is an important safety feature in any vehicle carrying liquids which can have the propensity to surge and suddenly shift weight and seriously affect the dynamic stability of the vehicle.

The climate in tropical Darwin has extensive periods of hot and humid weather and the Isuzu’s climate control air conditioning maintains a comfortable environment in the cab which is equipped with the familiar Isuzu multimedia system with 6.2inch screen, digital radio, DVD, MP3, voice-control and Bluetooth connection for easy smartphone integration.

Another feature of the Isuzu Traypack which impresses Scott is the turning circle.

“The turning circle is phenomenal and I can just turn it in a normal street. My girlfriend is an electrician and has a Ford Ranger which needs a three-point turn, but my truck just does it in one go,” he says.

Scott’s enthusiasm for the practicalities of his Isuzu Traypack cannot be overstated.

It is also important to him that any vehicle representing his business has to be professional in its appearance and the Traypack’s image has been further enhanced by NP Styles and Graphics.

“Personally I really can’t speak highly enough about it. It’s been awesome and worth every cent,” he says. “It looks and drives great.”

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