Description
Yato cordless impact wrench 850 Nm 4 Ah set includes a brushless 18-volt impact wrench with a 1/2″ (12.7 mm) square drive, two 4.0 Ah Li-Ion batteries, a charger and a 1/2″–1/4″ bit adapter. The maximum torque of the wrench is 850 Nm, a speed of 0–2350 min⁻¹ and the impact rate 0–2600 min⁻¹.
The impact mechanism converts the rotation of the brushless motor into short tangential impacts, so high torque is produced without a corresponding reaction torque being transmitted to the user’s hand. The wrench suits loosening and pre-tightening heavy bolted and nut joints, for example on vehicle wheels, chassis and steel structures.
The control panel selects three speed and torque levels for clockwise rotation, and for anticlockwise rotation either continuous mode or the intermittent Reverse self stop release mode, in which the drive rotates only briefly with each press of the trigger. How far the trigger is pressed adjusts the speed and torque steplessly, and the overload clutch disengages the drive at maximum torque. The wrench also has an LED work light and a direction switch.
The tool weighs 1.9 kg. The sound pressure level is 95 dB(A), the sound power level 103 dB(A) and vibration 16.1 m/s²; the insulation class is III and the IP rating IPX0. The batteries in the set have a charge level indicator, and the charger charges a 4 Ah battery in about 2 hours. The batteries are Yato 18V system slide-on batteries that fit the other tools in the range.
Uses and suitability:
The Yato cordless impact wrench 850 Nm 4 Ah is designed for heavy bolted and nut joints that require high torque and continuous use with two alternating batteries. The body-only model of the same wrench without batteries is the Yato cordless impact wrench 18V 850Nm, body only; for even higher torque, there is the Yato cordless impact wrench 18V 2400Nm + 6 Ah battery and charger.
- Wheel changing and tyre work: Loosening stuck wheel nuts and bolts; final tightening is done with a torque wrench to the manufacturer’s value.
- Vehicle and machinery repair: Large chassis, suspension and fixing bolts that need high torque to loosen.
- Steel structures and installations: Pre-tightening and dismantling bolted joints in brackets, flanges and machine parts.
- Screwing with the bit adapter: With the 1/2″–1/4″ adapter, the wrench can be used with impact bits when the lowest speed level is used.
Package contents:
- Impact wrench 18 V, 1/2″ square drive
- Bit adapter 1/2″ (12.7 mm) to 1/4″ (6.3 mm)
- Li-Ion battery 18 V 4.0 Ah, 2 pcs
- Charger 18 V
Features:
- Brushless motor: Efficient torque transfer and low mechanical wear.
- Three speed and torque levels: Selectable on the control panel for clockwise rotation.
- Reverse self stop: Intermittent release mode in which the drive rotates only briefly with each press of the trigger.
- Adjustable torque: How far the trigger is pressed adjusts the speed and torque steplessly.
- Overload clutch: Disengages the drive at maximum torque.
- Spindle brake: The drive stops quickly when the trigger is released.
- LED work light: Illuminates the work area.
- Reversing switch: Tightening and loosening with the same tool.
- Two batteries and fast charging: One battery charges while the other is in use; charging time about 2 h.
- Charge level indicator: Indicator operated by the button on the battery.
Technical specifications:
- Voltage: 18 V DC
- Drive: 1/2″ (12.7 mm) square
- Maximum torque: 850 Nm
- No-load speed: 0–2350 min⁻¹
- Stroke rate: 0–2600 min⁻¹
- Motor: brushless
- Hammer function: yes
- Adjustable torque: yes (3 levels on the control panel)
- Release modes: continuous / intermittent (Reverse self stop)
- Electronic speed control: yes
- Reversing switch: yes
- Spindle brake: yes
- Work light: LED
- Battery type: Li-Ion 18 V (Yato 18V system)
- Battery capacity: 4000 mAh
- Batteries included: 2
- Charger included: yes
- Charging time: 2 h
- Fast charging: yes
- Charge level indicator: yes
- Charger input: 200–240 V~, 50/60 Hz, 1.5 A
- Charger output: 21.5 V DC, 2.2 A
- Protection class: III
- IP rating: IPX0
- Sound pressure level LpA: 95.0 ± 3.0 dB(A)
- Sound power level LwA: 103.0 ± 3.0 dB(A)
- Vibration ah: 16.1 ± 1.5 m/s²
- Unit weight: 1.9 kg
- Maximum temperature of outer surfaces in use: 60 °C
- Battery storage: 0–30 °C, about 500 charge–discharge cycles
- Conformity: EN 62841-1, EN 62841-2-2, EN IEC 55014-1, EN IEC 55014-2
Yato cordless impact wrench 850 Nm 4 Ah user instructions:
1. Charging the batteries: The batteries are supplied uncharged. Slide the battery into the charger slot and plug the charger into a socket; the charger indicator light shows charging and a full battery. Charge indoors in a dry place under supervision.
2. Fitting the socket: Remove the battery. Choose a 1/2″ impact socket of the correct size for the fastener and push it onto the drive (or fit the 1/4″ bit adapter and an impact bit).
3. Fitting the battery and selecting the direction: Select the direction of rotation with the switch and slide the battery into the battery slot until the latch locks.
4. Selecting the mode: Use the control panel button to select a suitable clockwise speed and torque level. For anticlockwise rotation, you can select the intermittent Reverse self stop mode, in which the drive rotates only briefly with each press.
5. Tightening: Turn the bolt or nut by hand at least two turns. Hold the wrench with both hands, place the socket on the nut and press the trigger. When the impact mechanism starts hammering, release the trigger. Check the final torque with a torque wrench.
6. Loosening: Select anticlockwise rotation. If the breakaway torque of the fastener exceeds the maximum torque of the wrench, the overload clutch operates and the fastener does not loosen. Release the trigger and wait until the motor stops.
7. Maintenance: Remove the battery before maintenance. Clean the body and ventilation openings with compressed air (max. 0.3 MPa), a brush or a dry cloth without chemicals. Store the batteries at 0–30 °C at about 70% charge.
Warnings:
- Noise: Sound pressure level 95 dB(A), so wear hearing protection.
- Personal protective equipment: Wear safety glasses and protective gloves.
- Vibration: 16.1 m/s², so limit continuous use and take breaks.
- Battery out before changing the socket: Change the socket or adapter and carry out maintenance only with the battery removed.
- Impact sockets only: Ordinary sockets can crack in 850 Nm impact use.
- Overtightening: Continuous impacting tightens the joint further and can break the fastener; check the torque with a torque wrench.
- Hidden wiring: Hold the wrench by the insulated handles if the fastener may hit a live cable.
- Charger and batteries: Use only the supplied charger and Yato 18V batteries, charge in a dry place under adult supervision and do not short-circuit the battery terminals.
- Children: Keep the wrench, batteries and charger out of the reach of children.
Frequently asked questions (FAQ):
What is included in the Yato cordless impact wrench 850 Nm 4 Ah set?
A brushless impact wrench with a 1/2″ drive, a 1/2″–1/4″ bit adapter, two 18 V 4.0 Ah Li-Ion batteries and a charger.
What is the Reverse self stop function?
An intermittent release mode selected for anticlockwise rotation, in which the drive rotates only briefly with each press of the trigger. It makes controlled loosening of the fastener easier, so a loosened nut does not spin off the thread.
How long does it take to charge the battery?
The supplied charger charges a 4 Ah battery in about two hours. With two batteries, one can charge while the other is in use.
Can the wrench be used to tighten wheel nuts?
The wrench can be used to loosen and pre-tighten wheel nuts at the lowest level, but final tightening is always done with a torque wrench to the value specified by the vehicle manufacturer.
Do the batteries fit other Yato 18V tools?
Yes. The batteries are Yato 18V system slide-on batteries (YT-828461–YT-828465 range).
Recycling instructions:
The wrench and charger in the Yato cordless impact wrench 850 Nm 4 Ah set are electrical and electronic equipment that must not be disposed of with mixed waste; take them to a WEEE collection point. Take Li-Ion batteries separately to battery collection; tape the battery terminals before returning them to prevent short circuits. Sort the cardboard packaging into cardboard collection and the plastic parts into plastic collection.
