Stihl HS 45 Hedge Trimmer Manual

The Stihl HS 45 is a professional-grade petrol-powered hedge trimmer featuring a 45.4 cm (17.9 in) double-sided cutting blade, anti-vibration system, ergonomic handles, and a powerful 1.0 HP engine. Designed for heavy-duty trimming of hedges, shrubs, and bushes, it includes safety features like a throttle trigger lockout and a two-handed safety switch. Below are key sections for safety, features, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: Petrol engine, double-sided cutting blade, anti-vibration system, rear handle with throttle trigger, front handle, fuel tank, and spark plug.

Safety Instructions

Read all instructions before operation. Wear appropriate PPE.

1. Personal Protective Equipment: Always wear safety glasses, hearing protection, gloves, long trousers, and sturdy boots.
2. Clear Work Area: Ensure no bystanders, especially children or pets, are within 15 metres (50 ft).
3. Inspect Tool: Check for damage, loose parts, and blade condition before each use.
4. Fuel Safety: Refuel outdoors, with engine off and cool. Use approved petrol/oil mix. Wipe spills.
5. Two-Handed Operation: Keep both hands on handles during operation. Engage safety switches.

WARNING! Risk of serious injury or death from blade contact, kickback, or fire. Never operate with one hand or without proper training.

Assembly & First Use

Unpack and inspect contents. Assemble handle and blade guard if required.

1. Attach handle: Secure front and rear handles with provided bolts (if shipped separately).
2. Add fuel: Mix Stihl HP Ultra 2-stroke oil with unleaded petrol (50:1 ratio). Fill tank.
3. Start engine: Place on ground, engage choke (cold start), pull starter cord firmly until engine fires.
4. Warm-up: Allow engine to run at idle for 1-2 minutes before applying throttle.
5. Test controls: Ensure throttle trigger, lockout, and stop switch function correctly.

CAUTION! Ensure all fasteners are tight. Do not drop or impact the cutting blade.

Specifications

• Model: Stihl HS 45
• Engine Type: Single-cylinder two-stroke petrol engine
• Displacement: 27.2 cm³
• Power Output: 0.75 kW (1.0 HP) at 8,500 rpm
• Idle Speed: 2,800 rpm
• Maximum Blade Speed: 3,400 strokes per minute
• Fuel/Oil Ratio: 50:1 (Stihl HP Ultra oil recommended)
• Sound Pressure Level: Approx. 96 dB(A) (wear hearing protection)
• Vibration Level: < 2.5 m/s² (left/right handles)
• Warranty: 2 years commercial, 2 years private use (regional variations apply)

Controls and Operation

Main controls located on rear handle. Front handle for guidance and stability.

Rear Handle: Throttle trigger, throttle trigger lockout, stop switch (ON/OFF).

Starting Procedure: 1. Press fuel primer bulb (if equipped) 5 times. 2. Set choke lever to cold start position. 3. Hold rear handle firmly with right hand, place foot through handle brace. 4. Pull starter cord briskly until engine fires. 5. Move choke to run position. 6. Allow warm-up.

Stopping: Release throttle, press stop switch to OFF.

Adjustments: Carburetor settings pre-set at factory; only authorised dealers should adjust.

Fuel & Lubrication

Use fresh unleaded petrol (min. 90 RON) mixed with Stihl HP Ultra 2-stroke oil at 50:1 ratio.

1. Mix fuel in approved container: Add oil to petrol, shake thoroughly.
2. Refuel in well-ventilated area with engine off and cool.
3. Blade Lubrication: Apply Stihl hedge trimmer oil to blade before and during use to reduce wear.
4. Avoid spills: Wipe any fuel from unit before starting.

Tip: Use fuel within 30 days. Do not use old or contaminated fuel.

Cutting Techniques

For best results and safety, follow proper cutting methods.

1. Stance: Stand firmly with feet shoulder-width apart. Keep balance.
2. Grip: Hold front handle with left hand, rear handle with right. Thumbs wrapped around handles.
3. Cutting Motion: Use smooth, sweeping arcs from bottom to top of hedge.
4. Branch Size: Do not cut branches exceeding 20 mm (0.79 in) diameter.
5. Avoid Obstacles: Check hedge for wires, fences, or hard objects before cutting.
6. Kickback Awareness: Be prepared for sudden blade reaction if hitting thick wood.
7. Blade Angle: Keep blade parallel to hedge surface for even cut.
8. Overhead Cutting: Avoid cutting above shoulder height; use stable platform if needed.

WARNING! Never use the tip of the blade. Keep both hands on handles at all times.

Maintenance Schedule

Regular maintenance ensures performance and longevity.

Blade Sharpening: Have blade sharpened by authorised dealer when cutting performance declines.

Storage Guidelines

Prepare trimmer for storage to prevent fuel system damage.

1. Drain fuel tank: Run engine until it stops from fuel starvation.
2. Clean unit: Remove debris from blade, housing, and cooling fins.
3. Store in dry, secure location: Away from children, moisture, and extreme temperatures.
4. Blade protection: Apply light oil to blade and store with guard attached.

CAUTION! Never store with fuel in tank for more than 30 days. Use fuel stabiliser if necessary.

Warranty Information

Stihl HS 45 includes a warranty against defects in materials and workmanship. Standard warranty: 2 years for commercial use, 2 years for private use (check local regulations). Warranty does not cover damage from misuse, neglect, improper fuel, or unauthorised repairs. Keep purchase receipt for warranty claims. For service, contact an authorised Stihl dealer.

Troubleshooting

Service: For repairs beyond basic maintenance, contact an authorised Stihl dealer. Do not disassemble engine or carburetor.

Support: Stihl Incorporated, www.stihl.com, Customer Service: 1-800-467-8445