Traction engines were the hard workers of yesteryear — on and off road — though their weight and exceptionally slow speed means you won’t see them often. Our opportunity came at Easter’s Wheels at Wanaka Show.
The Burrell was the working man’s traction engine, and this is a 1924 Burrell, named Caduceus after a famous racehorse.
It takes two hours to get up enough steam to drive it. Fires are banked overnight to keep them hot. Top speed is a racy 15km/h transmitted to the wheels via a three-speed box.
This was the last Burrell imported. W Hayman of Opiro, near Waimate, bought it in the UK, and shipped it to Dunedin. It ended up in Southland where a district council used it to pull gravel from the Oreti River.
This was a road truck, 3.8m tall, with 1.981m wheels and a big belly water tank. It’ll hold 1000 litres of water, and weighs 16 tons. Old cut-down tyres are forced over the metal wheels as rubber’s a lot easier on modern tarmac.
The current driver is Ron Thomson. It was his uncle, Roy Hardwick, who bought it from the district council in the 1960s and restored it. Roy’s about 76 years old and remembers it when his father hired it for threshing.
Ron and Dave Hart, its engineer, reckon the machine puts out 64kW at the flywheel, but it’s not power that’s important with these things, it’s torque — pulling power. They say it would easily pull 50 tons if it could get traction.
You clamber three tall steps between the wheel and the fuel cache to ascend, where I start out on a bench hammered behind the wood box for a passenger.
The steering wheel takes 38 full turns, lock to lock — your family car is closer to three. I’m told it has suspension, but sitting out back with my feet on the logs of fuel, it didn’t feel like it.
There are no brakes. To slow, it’s pulled into reverse. That’s an improvement on the original braking that involved cranking a block of wood onto the flywheel. Usually it burst into flames, so they gave up on that.
Wood is still involved. To chock the wheels if you stop, a wooden block lowered by rope to the wheels or lifted by a driver.
There are two drivers. Ron starts off steering round the Wheels at Wanaka parade ground, and monitors the fire box by his feet, while Dave controls the whistle, gear lever and steam pressure. It runs on 200lb per sq in pressure, powering a double compound engine that uses the steam twice, first to power a 6in piston, before it drives a second 11in piston.
It’s noisy. Cogs and rods and the chains that transmit steering input to the front wheels are all clanking. It’ll use five litres of oil in a weekend to keep everything lubed and it towers over tractors around us.
Not surprisingly these things can be dangerous. The multiple pipes and valves include two parallel systems for functions such as getting water in.
“You can run out of fire,” Dave says, “It’ll just stop. But if you run out of water, you’ll explode.”
Then there’s that 150kg flywheel. “If the flywheel flew off while under way it’d be doing 80ft per second — or 88km/h. You wouldn’t catch up to that, it’d roll through your farmhouse and just keep on going”
I am given a turn at steering. There’s a “granny knob” on the wheel, and it takes lots of twirling through the large hoop to crank the wheels round. It’s like a slow boat — you start steering before you need to change direction, and cancel the turn before you need the prow to come round. Soon I’ve completed a couple of laps with Dave alongside controlling speed. Then we’re directed to do a lap four abreast. Our mighty rear wheel is just 30cm from the one beside us and keeping in tight formation when any touch will be painful is stressful.
But it’s also exhilarating. I’ve never felt so in charge of the road and everything on it.