Brush cutter advice & how-to
Practical, step-by-step help for getting the best from your brush cutter — starting, using, maintaining and staying safe.
In short:Our 109 brush cutter advice guides cover troubleshooting (a machine that won't start, cuts out or loses power), fuel, oil and carburettor care, line, heads and blades, servicing and winter storage, cutting technique and safety. Start with the essentials: how to start, use and maintain a brush cutter, how to change the line and how to cut safely. For petrol machines, most faults trace back to stale fuel, a blocked air filter or a fouled spark plug.
Start here — the essentials
How to start a brush cutter Cold and warm petrol starts, cordless start-up, and no-start fixes. Read → How to use a brush cutter The right cutting technique for grass, long growth and brambles. Read → Brush cutter maintenance Fuel, filters, plugs, cutting head and winter storage. Read → Brush cutter safety tips PPE, keeping bystanders clear and avoiding blade kickback. Read → How to change the line Choosing, winding and feeding new trimmer line, step by step. Read → How to choose a brush cutter The complete buying guide — type, engine, blades and more. Read →
Troubleshooting
Won't start, cuts out, loses power — diagnose and fix it.
- Brush cutter won't start: the 9 causes (and the fix for each)
- 4-stroke brush cutter leaking oil: causes and fixes
- Brush cutter blowing blue smoke: too much oil in the mix
- Brush cutter blowing white smoke: what it means
- Brush cutter dies at full throttle: causes and fixes
- Brush cutter gearbox getting hot: what to check
- Brush cutter hard to start when cold: causes and fixes
- Brush cutter hard to start when hot: the vapour-lock fix
- Brush cutter has no spark: how to test and fix the ignition
- Brush cutter keeps cutting out intermittently
- Brush cutter leaking fuel: where it comes from and how to stop it
- Brush cutter loses power under load: why it bogs down in thick grass
- Brush cutter making a rattling or knocking noise
- Brush cutter not cutting cleanly: why it tears grass
- Brush cutter only runs with the choke on: what it means
- Brush cutter overheating: causes, damage risk and fixes
- Brush cutter primer bulb not filling: causes and fix
- Brush cutter pull cord stuck or won't pull
- Brush cutter pull cord won't retract
- Brush cutter recoil hard to pull (but not seized)
- Brush cutter stalls once warm: the fixes
- Brush cutter starts then dies: why it cuts out after a few seconds
- Brush cutter vibrating excessively: find the cause fast
- Brush cutter won't idle: it dies when you release the throttle
- Brush cutter won't rev up: stuck at low revs
- Fuel not reaching the carburettor: how to diagnose
- How to read a brush cutter spark plug
- How to unflood a flooded brush cutter
- Why is my brush cutter backfiring?
Fuel, oil & carburettor
Mixing ratios, carb settings, filters and plugs.
- 2-stroke fuel ratio chart: 50:1, 40:1 and 25:1 in ml and litres
- Brush cutter carburettor screws explained: what L, H and T actually do
- Ethanol petrol (E10) and brush cutters: the damage and how to avoid it
- How to adjust a brush cutter carburettor (L, H and T)
- How to adjust brush cutter idle speed (the T screw)
- How to change a brush cutter spark plug (and read what it tells you)
- How to clean a brush cutter air filter (foam, felt and paper)
- How to clean a brush cutter carburettor without removing it (and with)
- How to clean a brush cutter fuel tank
- How to clean a brush cutter spark arrestor screen
- How to decarbonise a 2-stroke brush cutter exhaust
- How to drain old fuel from a brush cutter safely
- How to mix 2-stroke fuel for a brush cutter (step by step)
- How to replace a brush cutter carburettor
- How to store 2-stroke fuel safely
- Petrol vs battery brush cutter running costs compared
- What fuel does a brush cutter use? Petrol, octane and alkylate explained
Line, heads & blades
Fitting, sharpening and fixing the cutting gear.
- Brush cutter blade keeps loosening in use
- Brush cutter head keeps coming loose or unscrewing
- Brush cutter head types explained: bump feed, auto feed, fixed line and blade
- Brush cutter head won't spin: clutch, drive shaft and gearbox
- Brush cutter line keeps breaking: 7 reasons and the fixes
- Brush cutter line size guide: which diameter to use
- Brush cutter line welding or fusing together in the spool
- Brush cutter line won't feed out: bump feed and auto-feed fixes
- How to balance a brush cutter blade after sharpening
- How to fit a brush cutter blade correctly and safely
- How to load line in a bump-feed head
- How to remove a stuck brush cutter head
- How to replace a brush cutter clutch
- How to replace or fix a bent brush cutter shaft
- How to sharpen a brush cutter blade (file, grinder and balance)
- How to thread brush cutter line through the eyelets
- When to replace a brush cutter blade: 6 signs it is done
Servicing & storage
Keep it running for years — routine jobs and winter prep.
- Brush cutter clutch problems: slipping, dragging and how to fix
- Brush cutter maintenance schedule: what to do every use, month and year
- Brush cutter winter storage: the 8-step end-of-season routine
- How long does a brush cutter last?
- How much does a brush cutter service cost?
- How to break in a new petrol brush cutter
- How to check brush cutter compression
- How to clean a brush cutter after use (5 minutes that add years)
- How to grease a brush cutter gearbox (angle drive)
- How to replace a brush cutter fuel filter
- How to replace a brush cutter pull cord (recoil starter)
- How to service a brush cutter yourself: the full annual service
- How to transport a brush cutter safely (car, van and trailer)
- What to do if your brush cutter hits a rock or wire
Cutting technique
Brambles, slopes, edges and overgrown ground, done right.
- Brush cutter buying checklist: 10 things to check
- Brush cutter scything technique: the right cutting motion
- How to adjust a brush cutter harness correctly
- How to clear nettles with a brush cutter (and stop them returning)
- How to clear overgrown land with a brush cutter: a staged plan
- How to clear the bottom of a hedge with a brush cutter
- How to cut around fences, posts and walls without wrecking the line
- How to cut brambles with a brush cutter (without jamming it)
- How to cut long grass without clogging the head
- How to cut tall or wet grass with a brush cutter
- How to strim around obstacles, trees and posts safely
- How to strim around trees without killing them
- How to strim clean edges and borders
- How to use a brush cutter harness correctly
- How to use a brush cutter on a slope safely
Safety, noise & the law
PPE, hearing, vibration and what the rules say.
- Are brush cutters dangerous? The real risks
- Brush cutter blade kickback (blade thrust): what causes it and how to avoid it
- Brush cutter eye and face protection: mesh visor or goggles?
- Brush cutter injuries and first aid: what to do
- Brush cutter noise levels and hearing protection explained
- Brush cutter PPE: what you must wear (and what the law requires)
- Brush cutter safety distance: keeping people, pets and windows safe
- Brush cutter vibration and HAVS: exposure limits and how to protect yourself
- Can you use a brush cutter in the rain?
- Do you need a licence or training for a brush cutter?
- When can you use a brush cutter? Noise rules and permitted hours