Leaf Blower Won't Start | Fix Guide
Leaf blowers come in two-stroke and four-stroke varieties, each with different troubleshooting approaches. Whether you have a handheld Echo, backpack Stihl or battery-powered EGO, this guide covers all types to help you diagnose and fix starting problems.
Table of Contents
- Identify Your Engine Type
- Quick Diagnostic Checklist
- Two-Stroke Blower Issues
- Four-Stroke Blower Issues
- Battery Blower Issues
- Common Issues All Types
- Brand-Specific Problems
Identify Your Engine Type
Before troubleshooting, identify what type of blower you have.
Two-Stroke (2-Cycle)
- Mix oil with fuel (usually 50:1 ratio)
- No separate oil fill cap
- Lighter weight
- Higher RPM, louder operation
- Brands: Echo, Stihl, Husqvarna handheld and backpack models
Four-Stroke (4-Cycle)
- Separate oil reservoir with dipstick
- Use straight gasoline (no mixing)
- Heavier than two-stroke
- Quieter operation
- Brands: Honda, some Makita models
Battery-Powered
- No fuel or oil
- Lithium battery pack
- Quieter operation
- Brands: EGO, Ryobi, Greenworks, DeWalt, Milwaukee
[NEED REAL IMAGE: Blower engine type comparison]
Quick Diagnostic Checklist
Run through these checks before diving deeper:
| Check | Two-Stroke | Four-Stroke | Battery |
|---|---|---|---|
| Fuel fresh? | ✓ | ✓ | N/A |
| Oil level? | In fuel mix | Check dipstick | N/A |
| Battery charged? | N/A | N/A | ✓ |
| Kill switch ON? | ✓ | ✓ | ✓ |
| Choke correct? | ✓ | ✓ | N/A |
| Air filter clean? | ✓ | ✓ | N/A |
Two-Stroke Blower Issues
Two-stroke engines are common in professional and prosumer blowers. They require more attention to fuel quality.
Fuel Mix Problems
Two-stroke engines need oil mixed with gasoline. Wrong ratio causes problems.
Common ratios:
- 50:1 - Most modern blowers (Echo, Stihl, Husqvarna)
- 40:1 - Some older models
- 32:1 - Very old equipment
Symptoms of wrong mix:
- Too much oil: Blue smoke, fouled plug, hard starting
- Too little oil: Engine seizure, scoring
Solution: Drain old fuel completely. Mix fresh fuel at correct ratio. Use quality 2-stroke oil.
For more on fuel issues, see our small engine fuel problems guide.
Carburetor Problems
Small two-stroke carburetors clog easily from old fuel. Ethanol in modern gasoline accelerates this problem.
Symptoms:
- Won’t start at all
- Starts then dies
- Surges or hunts
- Bogs at full throttle
Solutions:
- Try starting fluid first - if it fires briefly, carburetor is the problem
- Remove and clean carburetor
- Replace diaphragms and gaskets
- Adjust mixture screws
See our how to clean a carburetor guide for detailed instructions.
For Stihl blowers, check our Zama carburetor repair guide.
Spark Plug Issues
Two-stroke plugs foul more readily than four-stroke due to oil in the fuel.
Symptoms:
- No spark
- Weak yellow spark (should be bright blue)
- Black, oily deposits on plug
Solution: Replace spark plug. Use correct type and gap:
- Most blowers: NGK BPMR7A or equivalent
- Gap: 0.020-0.025”
Fuel Lines and Filter
Two-stroke blowers have fuel pickup lines inside the tank that crack over time.
Symptoms:
- Won’t prime
- Loses prime quickly
- Hard starting after sitting
Solution: Replace fuel lines and in-tank filter. This is a common maintenance item on blowers over 2-3 years old.
See our fuel line replacement guide.
[NEED REAL IMAGE: Two-stroke blower carburetor]
Spark Arrestor Clogged
The spark arrestor screen in the muffler clogs with carbon over time.
Symptoms:
- Low power
- Won’t rev up
- Bogs at throttle
Solution: Remove and clean or replace spark arrestor screen.
Four-Stroke Blower Issues
Four-stroke blowers are less common but simpler in some ways - no fuel mixing required.
Oil Level Problems
Low oil triggers safety shutoff on most four-stroke blowers. This is the #1 cause of no-start on these engines.
Check: Dipstick should show oil between MIN and MAX marks.
Solution: Add oil if low. Use SAE 30 or 10W-30.
Fuel Quality
Same issues as two-stroke - old fuel causes carburetor problems.
Solution: Drain old fuel, add fresh. Four-stroke carburetors respond well to cleaning.
Valve Issues
Four-stroke engines have valves that can go out of adjustment.
Symptoms:
- Hard starting
- Loss of power
- Unusual engine noise
Solution: Check and adjust valve clearance per manufacturer specs.
Battery Blower Issues
Battery blowers have fewer failure points but different troubleshooting needs.
Won’t Turn On
Check:
- Battery fully charged?
- Battery seated correctly?
- Safety trigger engaged?
- Any error lights flashing?
Common fixes:
- Remove and reseat battery
- Clean battery contacts
- Try different battery if available
Short Runtime
Causes:
- Battery age (capacity decreases over time)
- Cold temperatures
- Running at maximum power constantly
Solutions:
- Use variable speed when possible
- Keep battery warm before use
- Replace aging batteries
For EGO blowers, see our EGO LB6504 problems guide.
For Ryobi, check our Ryobi 40V blower problems guide.
Motor Issues
Symptoms:
- Motor spins slowly
- Grinding noise
- Burning smell
Solution: Motor problems usually require professional service or replacement.
[NEED REAL IMAGE: Battery blower troubleshooting]
Common Issues All Types
These problems affect gas and battery blowers alike.
Dirty Air Filter
Clogged filters restrict airflow and cause rich running conditions.
Symptoms:
- Hard starting
- Black smoke (gas models)
- Loss of power
Solution: Clean foam filters with soap and water. Replace paper filters. Service every 25 hours or more often in dusty conditions.
Ignition System (Gas Models)
Testing spark:
- Remove spark plug
- Ground plug body against engine
- Pull cord while watching electrode
- Should see bright blue spark
No spark causes:
- Bad spark plug
- Failed ignition coil
- Kill switch grounded
- Wiring damage
Flooded Engine
Strong fuel smell indicates flooding.
Symptoms:
- Fuel smell from exhaust
- Wet spark plug
- Won’t fire
Solution:
- Set choke to OFF (open)
- Throttle to FULL
- Pull cord 10-15 times to clear excess fuel
- Wait 5 minutes
- Try starting with half choke
Starting Procedure
Correct starting procedure prevents many problems.
Cold Start (Gas Blowers)
- Set choke to FULL (closed)
- Set throttle to START or FAST IDLE
- Prime 5-8 times until fuel visible in bulb
- Pull cord until engine fires (may not run)
- Move choke to HALF
- Pull until engine runs
- Move choke to OFF when engine warms
Warm Start
- Choke OFF
- Pull - should start in 1-2 pulls
Flooded Start
- Choke OFF
- Throttle FULL
- Pull 10+ times to clear
- Return to normal start procedure
Brand-Specific Problems
Echo Blowers
Common issues on Echo PB series:
- Fuel line deterioration
- Carburetor diaphragm failure
- Spark arrestor clogging
See our Echo PB-9010T problems guide.
Stihl Blowers
Common issues on Stihl BR and BG series:
- Carburetor needs adjustment
- Fuel pickup clogging
- Ignition module failure
See our Stihl BGA 86 problems guide.
Husqvarna Blowers
Common issues:
- Smart Start system needs correct procedure
- Air injection system maintenance
- Fuel system service
See our Husqvarna 350iB problems guide.
Backpack Blowers
Backpack models have additional considerations:
- Throttle cable routing
- Fuel line length
- Hip throttle connections
See our backpack blower problems guide.
When to Get Professional Help
DIY-Friendly Repairs
- Spark plug replacement
- Air filter service
- Fuel line replacement
- Basic carburetor cleaning
- Battery replacement
Professional Service Recommended
- Internal engine damage
- Ignition coil diagnosis
- Carburetor rebuild with adjustment
- Compression testing
- Motor replacement (battery models)
Related Guides
- How to Clean a Carburetor
- Small Engine Fuel Problems
- Chainsaw Won’t Start
- String Trimmer Won’t Start
- Fuel Line Replacement
- Backpack Blower Problems
Summary
Most leaf blower starting problems come down to fuel issues. Old fuel gums up carburetors quickly, especially in small two-stroke engines. Check the basics first: fresh fuel, clean air filter, good spark plug. For battery models, verify the battery is charged and seated correctly. When carburetor cleaning doesn’t solve the problem, replacement carbs are affordable and often the best solution.