Installation Guide
Tools Needed:
- Adjustable wrench
- Screwdrivers (flat and Phillips)
- Pliers
- Socket set
- Oil funnel
Step-by-Step Assembly
- Unpack and Inspect: Remove all packaging materials and inspect for any shipping damage or missing parts.
- Handle Assembly: Attach the upper and lower handle sections using provided bolts and hardware.
- Install Wheels: Mount all four wheels onto the axle using the provided washers and cotter pins.
- Attach Grass Bag: Connect the grass collection bag to the rear discharge chute.
- Add Engine Oil: Fill the engine with SAE 30 motor oil to the proper level on the dipstick.
- Add Fuel: Fill the fuel tank with fresh unleaded gasoline (minimum 87 octane).
- Final Check: Ensure all bolts are tightened, wheels rotate freely, and safety features are operational.
Specifications
| Model Number | 20378 |
| Type | Gas-Powered Push Lawn Mower |
| Engine Type | 4-Cycle, OHV |
| Engine Power | 160cc |
| Cutting Width | 21 inches |
| Cutting Height | 1.5 to 4 inches (7 positions) |
| Fuel Capacity | 0.95 gallons |
| Oil Capacity | 20 oz (0.6L) |
| Starting System | Recoil Start |
| Weight | 65 lbs |
| Wheel Size | 8 inches (front), 10 inches (rear) |
| Grass Bag Capacity | 2.5 bushels |
Warranty Information
- Full Warranty: 2 years residential use
- Engine Warranty: 3 years on Toro engine
- Commercial Warranty: 90 days commercial use
For warranty service, contact Toro Customer Service at 1-888-384-9939 or visit Toro.com
Key Features
Personal Pace® System
Toro's innovative Personal Pace system automatically adjusts the mower's speed to match your walking pace, providing effortless control and superior maneuverability.
4-Cycle OHV Engine
The powerful 160cc overhead valve engine delivers reliable performance with reduced emissions and noise compared to traditional 2-cycle engines.
Quick Stop® Blade Brake System
Safety system that stops the blade within 3 seconds when the handle is released, while allowing the engine to continue running for transport.
Folding Handle
Easy-fold handle design allows for compact storage in garages or sheds, saving valuable space when not in use.
7-Position Height Adjustment
Single-lever cutting height adjustment allows quick changes to 7 different cutting positions from 1.5 to 4 inches.
3-in-1 Discharge System
Mulch, bag, or side discharge capability allows you to choose the best method for your lawn care needs and conditions.
Cutting System Explained
Mulching
Fine cuts clippings and returns them to lawn as natural fertilizer
Bagging
Collects clippings in 2.5 bushel bag for clean, debris-free finish
Side Discharge
Discharges clippings to the side for longer grass or wet conditions
Height Adjustment
Single lever controls all four wheels for consistent cutting height
Blade Design
High-lift blade creates strong vacuum for superior grass lift
Deck Design
21-inch steel deck with optimized airflow for even cutting
Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Engine won't start | Empty fuel tank, stale gasoline, clogged air filter | Add fresh fuel, clean/replace air filter, check spark plug |
| Poor cutting performance | Dull blade, incorrect cutting height, engine speed too low | Sharpen/replace blade, adjust cutting height, check throttle setting |
| Uneven cutting | Uneven tire pressure, bent blade, uneven deck | Check tire pressure, inspect/replace blade, level mower deck |
| Excessive vibration | Damaged blade, loose blade bolt, debris under deck | Inspect blade, tighten blade bolt, clean mower deck |
| Engine runs rough | Dirty air filter, water in fuel, clogged fuel line | Clean air filter, drain fuel tank, check fuel line |
| Wheels not turning | Debris in wheel gears, damaged drive cable | Clean wheel mechanisms, inspect drive cable |
Maintenance Schedule
- Before each use: Check oil level, tire pressure, blade condition
- Every 25 hours: Clean air filter, check spark plug
- Every 50 hours: Change engine oil, sharpen blade
- Every 100 hours: Replace air filter, spark plug
- Season end: Drain fuel or add stabilizer, clean thoroughly
- Season start: Change oil, check all components
Manual Downloads
Current Model Manuals
20378
21" Personal Pace® Mower
20379
21" Recycler® Mower
20380
22" Super Recycler®
20381
21" Electric Start
Popular Previous Models
20370
21" Standard Mower
20372
22" Recycler®
20374
21" Briggs Engine
20376
22" Commercial