The Z994R is powered by a 3-cylinder, liquid-cooled diesel engine with gross SAE J1995, PS 24.7 hp (18.4 kW) rated power at 3200 rpm that meets U.S. Environmental Protection Agency (EPA) Final Tier 4 emission standards:

High-torque, low-emission diesel engine for strong performance in the toughest conditions

Low vibration and noise levels

Isolated with rubber mounts for a smoother operator ride

Superior fuel economy

High torque reserve for plenty of power and performance

Key features of the engine include:

Economical, cast-in block cylinder design provides good cooling and long life.

Liquid-cooled design provides more consistent operating temperatures than air-cooled.

Fuel filter with replaceable element is provided.

Indirect fuel injection uses a pre-combustion chamber to give the engine smooth and quiet operation.

Full-pressure lubrication with full-flow filter lengthens engine life. Engine wear reduced by ensuring proper lubrication, even when operating on hillsides or uneven terrain. Oil filter helps keep oil clean for increased engine life.

Aluminum alloy pistons with built-in steel struts are lightweight to reduce connection rod bearing loads and provide good heat-transfer characteristics. Design permits tighter tolerances and neutralizes expansion of the piston, thereby reducing blow-by fuel and noise from the piston slap. Higher top rings on the piston and a thinner head gasket greatly reduce the volume of unburned waste and increase combustion efficiency.

Timing gears and injector drive gears utilize helical profile gears to help lower engine noise. Gear teeth have a ''roll-off'' profile, giving almost no clash, no noise, and no backlash.

Glow plugs provide quick starts in temperatures down to -18°C (0°F)

Key start and shutoff eliminate fuel shut-off knob; electric solenoid shuts fuel supply off immediately when key is turned off.

Air cleaner with secondary safety element and restriction indicator

Dual-element, dry-type air cleaner with safety element and air service indicator Dual-element design for added engine protection and easy service Completely sealed for effective cleaning Ninety to 95 percent of dirt ejected before it reaches the paper element

Air cleaner restriction indicator to let operator know when the filter needs servicing

Radiator

A sealed radiator compartment controls trash and debris. A cover is provided over the radiator, and a cooling fan area controls the flow of air.



Knobs on both ends of the cover hold it in place.

An automotive-type radiator, coolant reservoir, and electric cooling fan are provided to remove heat from the engine coolant:

The cooling fan is thermostatically controlled so it only runs when necessary.

See-through coolant recovery tank permits the operator to check the coolant level without removing the radiator cap.

A debris screen with a corrugated shape to give a large surface area covers the intake air side of the radiator to keep the radiator fins clean.



The debris screen can be easily removed for cleaning, if desired, and also for access to the radiator fins.

Fuel tank

The Z994R Diesel ZTrak™ Mower is equipped with a single 11.5-U.S. gal. (43.5-L) fuel tank that provides enough capacity to allow mowing for a full day without refueling:

Large, angled filler neck makes for easier refueling

Fuel cap tether is provided to secure the filler cap while refueling

Fuel gauge is provided as standard equipment

NOTE: The fuel fill level is 1 in. (25 mm) below the bottom of the filler neck.

Gearbox cooling fins and fan

A right-angle gearbox is used to convert power from the horizontal shaft diesel engine to vertical shaft power to operate the vehicle transmission and the mower power-take off clutch. Cooling for the gearbox is provided by fins on the gearbox housing and a fan.