This document is an instruction manual for the Webb 40cm Petrol Scarifier & Aerator, model WEPS400 (Product No. 1938317002).

Function Description

The Webb 40cm Petrol Scarifier & Aerator is a walk-behind petrol-powered machine designed for private use in home and gardening environments. Its primary function is to rip out moss and weeds, complete with their roots, and to loosen the soil in medium to large lawns. This process, known as scarifying or dethatching, helps the lawn absorb nutrients better and promotes overall health. The manual recommends scarifying in spring (April/May) and autumn (October). The aerator function involves the cylinder rotating and combing the lawn or aerating slightly mossy areas, which improves water drainage and facilitates oxygen absorption. Scarifying can be done throughout the growing period as needed. The equipment is not designed for commercial, trade, or industrial applications, with an annual operating time generally not exceeding 50 hours for private use.

Important Technical Specifications

Model No.: WEPS400
Product No.: 1938317002
Working Width: 400 mm
Working Depth: 8 settings (5 to -15 mm)
Collector Capacity: 45 Litre
Scarifier Blades (Total): 18 pcs
Scarifier Blade Diameter: 166 mm
Aerator Tines (Total): 28 pcs
Aerator Tines Diameter: 141 mm
Engine: DH212 (Product No. 1938298001)
Fuel Type: Unleaded Petrol
Engine Displacement: 212 cc
Engine Power (Max): 4.3 kW
Working Speed: 2800/min
Rated Speed: 3600/min
Full Tank Capacity: 3.6 L
Required Engine Oil Level: 0.6 L
Measured Sound Power Level: 95 dB(A)
Guaranteed Sound Power Level LWA: 98 dB(A)
Vibration Level: Left Handle 19.7 m/s², Right Handle 24.98 m/s²
Total Weight: 34 kg

The manufacturer reserves the right to change product specifications and livery for continuous product improvements.

Usage Features

The machine requires assembly by a minimum of two persons. It is a 4-stroke engine powered machine and is shipped without petrol or oil. Users MUST fill the engine with recommended 4-stroke SAE30 or 10W/30 air-cooled lawnmower engine oil before starting. Fresh unleaded petrol (under 30 days old, E10 compatible, Octane rating 87/91 RON or higher) must be used. Do not mix oil with fuel.

Starting the Engine (Cold):

Place height adjuster into its highest position.
Check engine oil.
Fuel the engine with unleaded fuel.
Move the fuel tap to the OPEN position.
Move the Choke lever to the CLOSED position.
Pull the OPC/Brake lever towards the top handle.
Grab the recoil starter handle and pull lightly until resistance is felt, then pull rapidly.
Allow the engine to warm up briefly, then set the choke lever to the OPEN position.
The blades/tines will now rotate. Lower to the required height using the height adjuster.

Starting the Engine (Warm):

Place height adjuster into its highest position.
Move the fuel tap to the OPEN position.
Move the Choke lever to the OPEN position.
Pull the OPC/Brake lever towards the top handle.
Grab the recoil starter handle and pull lightly until resistance is felt, then pull rapidly.
The blades/tines will now rotate. Lower to the required height using the height adjuster.

Stopping the Engine:

Release the OPC/Brake lever to stop the engine.
Close the fuel tap. The blades/tines will continue to rotate for a few seconds after the motor is switched off. Do not attempt to stop the cassette manually.

Working Depth Adjustment: To set the working depth, push the height adjuster lever gently away from the deck and move it up or down to the desired depth, then lock the lever back into position. Moving the lever to the right raises the blade, and to the left lowers it from 5 to -15mm.

Transport: When moving the machine, always ensure the height adjustment lever is placed in the highest cutting height to prevent blades/tines from contacting the ground.

Cylinder Changing: The equipment can be assembled with either dethatching (blades) or scarifying (spring tines) cylinders. Only genuine Webb products should be used for replacement. This procedure requires a minimum of two adults and suitable hard-wearing gloves. Steps involve removing the belt cover, bottom pulley, blade belt, loosening bearing mounting blocks, sliding out the cylinder, and then reversing the process with the new cylinder.

Maintenance Features

General Recommendations:

Always observe safety rules.
The warranty does not cover operator abuse or negligence; proper maintenance is required for full warranty value.
All adjustments should be checked at least once per season.
Changing the engine-governed speed will void the engine warranty.
Always stop the engine, disconnect the spark plug, and ground the spark plug cap before any maintenance.

Lubrication:

Lubricate pivot points on the OPC/Brake lever at least once per season with general maintenance spray.
Lubricate wheels at least once per season with general maintenance spray.
Oil cables at regular intervals and check for easy movement.

Engine Oil Check/Add:

Remove and wipe the dipstick.
Insert the dipstick without screwing it in.
Remove and check oil level (should be between MIN and MAX marks).
If low, add 4-stroke SAE30 or 10W/30 air-cooled lawnmower engine oil slowly (0.6L capacity). Do not overfill.
Wait one minute, recheck, then replace and tighten the dipstick.

Below 40°F (4°C), SAE 30 may cause hard starting.
Above 80°F (27°C), 10W-30 may cause increased oil consumption; check oil level more frequently.

Changing the Oil: Change engine oil annually before the season starts, when the engine is warm.

Place an oil drip tray beneath the oil drain screw.
Remove the oil filler screw.
Undo the oil drain screw and drain oil into a container.
Close the drain screw.
Add new recommended engine oil slowly (0.6L capacity).
Wait one minute, recheck, then dispose of used oil according to regulations.

Spark Plug: Inspect spark plug visually; discard if cracked or chipped. Measure gap (0.76mm) with a feeler gauge and adjust if necessary. Attach washer, thread plug by hand, then tighten with a wrench (1/2 turn for new, 1/8-1/4 turn for old). An improperly tightened plug can damage the engine.

Air Filter: Check air filter every 50 hours of use, or more frequently in dusty conditions.

Remove the air filter.
Clean with compressed air or by tapping it. Do not use petrol or flammable solvents.
Assemble in reverse order.

Cleaning:

Engine Care: Clean the engine regularly with a cloth or brush to ensure proper air circulation. Remove grass, dirt, and debris from the exhaust area. Do not use a water hose or pressure washer on the engine.
Deck Care: Clean the underside of the machine after each use to prevent build-up. Disconnect the spark plug cap. Drain petrol or tip the scarifier/aerator on its side (air filter housing facing up) to clean the underside with a tool.

Storage & Transport:

Empty the fuel tank. Disconnect the spark plug cap. Drain petrol or tip the machine on its side (air filter housing facing up).
Change oil while the engine is still warm.
Clean engine surface debris.
Remove spark plug, place 1 teaspoon (5 ml) of oil into the hole, pull starter rope 8-10 times to coat the cylinder bore and piston, then replace spark plug.
Store in a dry, clean, frost-protected place, out of reach of unauthorized persons and direct sunlight.
Rust-proof equipment with light oil or silicone, especially cables and moving parts.
Do not store fuel for longer than 30 days as it can become stale and damage the carburetor.

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