Having spent his formative years driving HGVs, Niall Turley doesn’t always turn to tractors for powering implements on his family’s dairy farm near Camlough, County Armagh.

So much so that when a new mixer wagon was required to feed the 80 cows he milks with dad Brian and brother Brendan, he suggested they mount it on the back of a retired bin lorry.

By his reckoning, this would be cheaper to buy than a tractor of equivalent age, use less fuel and be more manoeuvrable.

See also: Keenan mixer wagon renovator offers repair tips

As relative newcomers to dairy – having expanded from farming sucklers – the Turleys were able to think carefully about their setup rather than being lumbered with old infrastructure.

For this reason, they opted for a Lely AJ robot rather than a conventional parlour and designed the layout of their cubicle shed for peak efficiency.

The lorry-mounted wagon was another key part of the plan. “It’s a machine we have to use every day, so we thought we’d make the most convenient setup we could,” says Niall.

“We’d need to have a tractor dedicated to the job, so why not make it self-propelled.”

Keenan wagon

As fans of horizontal beater wagons, they opted for a high-spec Keenan Mechfiber 320+ complete with an In Touch control system.

And because there was no need for a drawbar or wheels, it came on a steel frame ready to bolt onto the lorry chassis, which shaved a little off the purchase price.

Fitted with a 14cu m hopper, this has ample capacity to feed their herd in one go and is large enough to cope if they want to increase cow numbers at any point.

When it came to the truck, a bin lorry was the by far the best candidate.

Not only are these compact, but the cab is low to the ground, meaning access is easy, they already have a hydraulic system and there’s often a steering rear axle, which vastly improves manoeuvrability.

After hunting around online, they found a suitable candidate for sale at an auction in Wales – a 2014 Dennis Eagle Elite packing a 320hp Volvo six-cylinder engine allied to a six-speed automatic ZF transmission.

This shifts between drive, neutral and reverse simply by pressing buttons on the dash, making direction changes particularly swift – perfect for shunting back and forth in the feed passage.

In an ideal world, they’d have opted for a left-hand drive model to give a better view of the chute, but they figured a carefully positioned camera would alleviate any blind spots.

This would be easy enough to do as the truck was already fitted with a 360deg camera system which just needed a bit of repositioning.

With a modest 50,000km on the clock, the truck was tidy and barely run in, so they bought it blind and had it shipped over.

Then the work could begin. Once the dust cart body and extensive wiring loom had been removed, the wagon was offered up.

There was plenty of space to mount it, and it was simple to bolt in place, but they did have to shift it back slightly to make room for the front doors to open for servicing.

More of a challenge was hooking up a pto to drive the mixer paddles, and getting other hydraulic and electrical services to play ball.

Hydraulic pto

As there was already a hydraulic pump on board, they went hunting for a motor that had enough power to turn the wagon’s input shaft at 540rpm.

After some painstaking research, they found an Aber unit that was up to the task, along with a suitable reduction gearbox to give enough torque for it to start under load.

All was looking good until they realised the truck’s pump didn’t have enough oomph to spin it at 540prm.

Finding a replacement for this was also tricky, but they eventually tracked down a dual unit – one side to run the pto and the other for further hydraulic services – that was almost big enough.

They then stripped it down and fitted bigger vanes, which finally gave the output they needed.

As the pto is live drive, oil is constantly flowing around the system. So, in order to put the wagon in and out of work, they ran the pipes into the cab and fitted a simple diverter valve.

“We could have gone down the route of fitting an electric version, but we wanted to keep the setup as simple as possible to reduce the chance of breakdowns,” says Niall.

They even came up with a plan for feeding if the lorry wouldn’t start, adding hydraulic connections so that it could be powered by a tractor.

This would mean the ration would need be loaded onto the yard and fed out with a bucket, but it would keep them going.

“We’ve also got an old Keenan 140 back-up wagon, so there are options if it ever gave us trouble.”

Two other hydraulic services were hooked up – one for the chute and one for the door – which are operated by another hydraulic block positioned in the cab.

The result of running all these services into the cab meant there was a spaghetti-like tangle of hydraulic pipes between the seats.

To hide these away, an aluminium centre console was fashioned with neat openings for a pair of spool levers and the pto’s diverter valve.

Electrical headaches

All was looking good at this point, apart from the fact that the removal of the dust cart’s original, very complicated, wiring loom had put the truck’s electrics into lockdown.

Hours were spent trying to sort this out, to no avail.

“We were pretty fed up by this point, but then we had a brainwave… we dug the old loom out of the skip, plugged it in and everything immediately came to life,” says Niall.

“We then methodically went through disconnecting wires, until we found the one that shut it down.

“As soon as this connection was made in the box of electrics on the side, it was sorted and we’ve kept it firmly shut ever since.”

In-cab upgrades

Once the electrics were behaving, they could concentrate on the finishing touches, such as fitting a second display in the cab so that they can keep an eye on how much feed is being dispensed.

They also fashioned a rudimentary hand throttle to get the engine revs up to the 1,200rpm required to achieve 540rpm.

Currently this is just a bolt that is wound down to put pressure on the foot throttle, but they are considering drafting in some help to add an electric switch.

Outside, they smartened things up by making their own aluminium chequer plate mudguards using a home-made bending tool, as well as adding a custom Beefy flap at the rear.

Solid performance

Since the project was completed in July 2023, the rig has been working flat out and has proved far handier than running a wagon behind a tractor.

“It’s so quick to nip around the yard and buildings and fuel use is incredibly low – we feed with it once a day and it only uses 160 litres over five weeks.”

No modifications are planned other than the hand throttle, but their only regret is not getting Keenan to mount it on a shallower frame.

“It’s totally unnecessary as the lorry chassis provides all the strength and it makes the tub sit higher than it needs to,” says Niall.

“Thankfully, we don’t have a problem with the height in our sheds, but it’s the one thing that could have been better.”