Kubota AD70 Tiller Operator's Manual
This operator's manual is the factory operation and maintenance reference for the Kubota AD70 walk-behind diesel tiller and its Kubota E70-TB engine, running roughly 32 pages of safe-operation guidance, control identification, operating procedure, routine maintenance, and field adjustment. It's the book that came with the machine: how to start and run the engine, how to set tilling depth and tine speed, how to service the air cleaner, fuel filter, and battery, and how to adjust the power and wheel clutches. Originally published by Kubota and delivered here as an instant PDF download you can read on any device or print for the cab.
Models covered: Kubota AD70
About the Kubota AD70
The AD70 is a center-drive walk-behind rotary tiller powered by the Kubota E70-TB — a horizontal, water-cooled, four-cycle diesel of 309 cc (18.86 cu. in.) rated at 7.0 hp (SAE gross) at 2,500 rpm. It uses a precombustion swirl-chamber combustion system, forced lubrication with a trochoid pump, a BOSCH “mini” type injection pump with a BOSCH “throttle” type nozzle, and a cyclone-type centrifugal air cleaner, with electric starting and glow-plug preheat. The machine runs three forward travelling speeds and one reverse, a tilling width of 500 mm (20 in) — 630 mm (24.8 in) optional — a 360 mm rotor, and a depth regulator adjustable from 1 to 7 inches in 1-inch increments.
At about 200 kg (440 lbs) with a three-stage vertically adjustable, swinging handlebar and a tine-clutch lockout that prevents shifting to reverse while the tines are turning, the AD70 is a purpose-built diesel garden tiller. Machines like this stay in service for decades because the diesel powerplant is durable and economical, which is exactly why the original operating and maintenance procedures still matter — knowing the correct starting sequence, lubrication points, and clutch adjustments keeps the unit running as designed.
What This Manual Covers
- Safe Operation: Before-starting, operation, transporting, maintenance, and storage safety, plus an illustrated guide to the tiller's safety labels and their part numbers, and care of safety signs.
- Servicing of Tiller: Where the tiller and engine serial numbers are located and how to record them for parts and service.
- Specifications: Full specification table for the AD70 and the E70-TB engine, plus travelling speeds and axle rotating speeds at 2,500 engine rpm.
- Controls: Identification and function of the power clutch lever, wheel clutch levers, travelling speed shift lever, tine rotation direction shift lever and tine clutch, engine speed and shutoff levers, starter switch, glow plug controller, fuel cock, and handle levers.
- Operating Instructions: Pre-start checks, starting and stopping the diesel engine (including preheat times by ambient temperature), adjusting the handle, changing tine speed, adjusting tilling depth, mounting the tiller tines and furrower, and using the rear-cover hook.
- Maintenance: Daily check, maintenance check list, lubrication and points to be lubricated, air cleaner and fuel filter service, wheel tube and blade shaft nuts, battery inspection, radiator, tiller cleanliness, and inspection of fuel lines and wiring.
- Adjustments: Adjusting the power clutch, fan belt tension adjustment and replacement, adjusting the wheel clutch, wheel tread width and wheel replacement, and tire air pressure.
- Storage: Preparing the tiller for storage.
Why This Manual Matters
- Correct diesel starting and preheat procedure. The manual documents the exact starting sequence, oil-pressure indicator behavior, and glow-plug preheat times by ambient temperature — the details that keep a cold-weather start from turning into a no-start.
- Machine-specific settings you need at the handles. Tilling depth in 1-inch increments to 7 inches, tine speed selection, and the travelling-speed/tine-clutch lockout are all explained so you operate the AD70 the way it was built to run.
- The maintenance schedule the machine depends on. A daily check and full maintenance check list cover the air cleaner, fuel filter, battery, radiator, and lubrication points, so routine service happens on time rather than after a failure.
- Adjustment procedures spelled out. Power clutch, wheel clutch, and fan belt tension adjustments are step-by-step, which is what you need when the controls drift out of spec with use.
- Long service life, scarce documentation. Diesel walk-behind tillers like the AD70 are still working machines, but the original operator literature is increasingly hard to find — this searchable, restored PDF puts it back in your hands.
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