LB700 Corded Blower Losing Power? Here's What to Check
The Black and Decker LB700 is a 180 MPH corded electric blower that costs under $30 and produces 180 CFM of airflow. Common problems include the motor not starting (check the outlet and extension cord—use 14-gauge or heavier for runs over 50 feet), reduced power (debris in the intake or worn motor brushes) and broken tubes (replacement parts available for $10-15). The 2-year warranty covers manufacturing defects but not wear items.
Overview of the Black and Decker LB700
The LB700 is designed for light-duty use at an entry-level price point.
| Specification | Value |
|---|---|
| Motor | 7 amp |
| CFM | 180 |
| MPH | 180 |
| Weight | 4.4 lbs |
| Cord | User-supplied extension required |
| Warranty | 2 years |
The LB700 delivers basic blowing power at a budget-friendly price
Best for: Small yards, driveways, patios, decks, garages and light debris. This is not designed for heavy leaf coverage or large properties - think of it as a broom replacement, not a professional landscaping tool. For more power, see our backpack blower problems guide.
Key advantages:
- Extremely affordable (under $30)
- No fuel, oil, or battery to manage
- Lightweight and easy to handle
- Simple design with few parts to fail
- Instant power - no starting procedure
Power Problems with the Black and Decker LB700
Won’t Turn On
Check in order:
- Outlet power - Test with another device
- Extension cord - Must be 14-gauge or heavier for full power
- Cord connections - Check both ends
- Trigger switch - Press firmly
Extension cord requirements:
- Up to 50 feet: 16-gauge minimum
- 50-100 feet: 14-gauge minimum
- Over 100 feet: 12-gauge required
Intermittent Power
Cuts in and out:
- Extension cord connection loose
- Cord damaged internally
- Trigger switch worn
- Internal wire connection
Test with different extension cord first - most common cause. A circuit tester can verify outlet power quickly.
Trips Circuit Breaker
Blower starts but breaker trips:
- Circuit overloaded (other items on same circuit)
- Extension cord too long or too thin
- Motor issue drawing excessive current
- Outlet/wiring problem
GFCI Outlet Trips
Ground fault interrupt triggers:
- Moisture in connections
- Damaged cord insulation
- Internal motor short
- Normal GFCI sensitivity with motors
Try non-GFCI outlet if available. Some GFCI outlets are overly sensitive to motor startup surge.
Motor Issues in the Black and Decker LB700
Motor Won’t Run
Power present but no motor:
- Trigger switch failed
- Motor brushes worn (if brush motor)
- Motor windings damaged
- Thermal overload tripped
Motor Runs Slow
Less speed than normal:
- Extension cord too light gauge
- Low voltage at outlet
- Motor brushes worn
- Bearing drag
Motor Overheats
Gets hot and shuts off:
- Extended continuous use
- Blocked intake
- Internal motor issue
- Ambient temperature high
Allow 15-30 minutes to cool. This is a light-duty tool - not designed for extended continuous operation.
Unusual Motor Sounds
Grinding: Bearing failure likely Sparking visible: Brush motor normal, excessive = problem High-pitched whine: Normal under load
Motor Smells
Burning smell:
- Stop immediately
- Check for debris wrapped around motor
- Motor may be failing
- Don’t continue use
Performance Insights for the LB700
Weak Airflow
Less output than expected:
- Extension cord inadequate
- Intake blocked
- Tube not connected
- Internal obstruction
Speed Control Issues
If equipped with variable speed:
- Clean dial/trigger
- Check connections
- Speed controller may be failing
Tube Problems
Tube won’t stay on:
- Check connection method
- Clean mating surfaces
- Inspect for cracks
- May need replacement
Physical Concerns with the LB700
Trigger Problems
Sticking or non-responsive:
- Clean trigger area
- Check for debris
- Switch may be worn
- Internal connection issue
Handle Vibration
Excessive vibration:
- Normal for this price point
- Check for loose parts
- Fan may be unbalanced
- Bearing wear
Cord Management
Cord gets in the way:
- Use cord retention hook if equipped
- Route cord over shoulder
- Work away from outlet
- Use proper length extension
Maintenance Tips for the LB700
After Each Use
- Unplug
- Clear debris from intake
- Wipe exterior
- Coil cord properly
Monthly
- Clean intake thoroughly
- Inspect cord for damage
- Check tube condition
- Clean trigger area
Annually
- Complete inspection
- Check all connections
- Verify cord integrity
- Replace if worn
Storage
- Store indoors
- Protect cord from damage
- Keep clean and dry
- Avoid temperature extremes
Signs It’s Time to Replace Your Blower
At under $30, the LB700 is often cheaper to replace than repair.
Replace when:
- Motor fails
- Switch fails
- Burning smell
- Cord damage at tool
May be worth fixing:
- Extension cord issue
- Tube replacement
- Intake cleaning
Safety Considerations for Using a Blower
Corded blower safety:
- Always use grounded outlet
- Inspect cords before each use
- Don’t use in wet conditions
- Keep cord away from blower path
- Unplug before any maintenance
Troubleshooting the Black and Decker LB700
| Problem | Likely Cause | Solution |
|---|---|---|
| Won’t turn on | No outlet power | Test outlet |
| Won’t turn on | Bad extension cord | Try different cord |
| Intermittent power | Loose cord connection | Check connections |
| Trips breaker | Overloaded circuit | Use dedicated circuit |
| Trips GFCI | Motor sensitivity | Try non-GFCI outlet |
| Runs slow | Undersized cord | Use heavier gauge |
| Overheats | Extended use | Let cool 15-30 min |
| Weak airflow | Blocked intake | Clear debris |
| Burning smell | Motor failing | Stop use immediately |
| Excessive vibration | Fan imbalance | Check for debris |
Common Questions About the LB700
Is the LB700 powerful enough for my needs?
For small areas, driveways, patios and light leaves, yes. The 180 CFM output handles dry leaves and light debris effectively. It’s not designed for large yards, heavy leaf coverage, or wet debris. Think of it as a powered broom rather than a professional landscaping tool.
Why do I need a heavy-gauge extension cord?
Thin extension cords can’t deliver full current to the motor. The result is a motor that runs weak and a cord that heats up dangerously. For the LB700’s 7-amp motor, use at least 14-gauge cord for runs up to 100 feet. Longer runs need 12-gauge. Using the right cord makes a noticeable difference in performance.
How long should an LB700 last?
With typical light residential use (clearing driveways, patios and small areas), 3-5+ years is reasonable. Heavy or extended use shortens lifespan. Store it indoors and keep the intake clear to maximize longevity.
Should I repair or replace a broken LB700?
At under $30, replacement usually makes more sense than any significant repair. If the motor fails, switch fails, or there’s internal damage, buy a new one. Simple fixes like trying a different extension cord or clearing debris are worth attempting first.
Why does my LB700 trip the GFCI outlet?
GFCI outlets are sensitive to the electrical characteristics of motor startup. The initial surge when the motor starts can trigger some GFCI circuits even when nothing is wrong. Try a non-GFCI outlet if available, or use a longer extension cord to reach a regular outlet.
Can I use the LB700 on wet leaves?
Not recommended. Wet leaves are much heavier than dry ones, and the LB700’s 180 CFM isn’t enough to move them effectively. Wait for leaves to dry, or use a more powerful blower for wet debris.
Use the right gauge extension cord for full power and safety
Related Guides
- EGO LB6504 Leaf Blower Problems
- Ryobi 40V Blower Problems
- Leaf Blower Won’t Start
- Backpack Blower Problems
The Black and Decker LB700 does one job well at a bargain price. Use a proper extension cord, keep the intake clear, and it handles light leaf duty reliably for years. When it eventually wears out, the low replacement cost means you’re not out much.