toro model 20037 manual

The Toro Model 20037 is a high-performance walk-behind lawn mower featuring a 21-inch cutting deck, 6.75 ft-lbs torque Briggs & Stratton engine, 3-in-1 cutting system (mulch, bag, side discharge), adjustable cutting height (1.5-4 inches), single-lever height adjustment, easy-start system, durable steel deck construction, and rear-wheel drive. Designed for residential use on medium to large lawns. Below are key sections for safety, features, assembly, operation, maintenance, and troubleshooting.

1. Features at a Glance 2. Assembly Instructions 3. First-Time Setup 4. Specifications 5. Controls and Operation 6. Cutting System Setup 7. Maintenance Procedures 8. Storage Guidelines 10. Regulatory Information 11. Troubleshooting

Features at a Glance

Key components: 21-inch steel cutting deck, Briggs & Stratton engine, 3-in-1 cutting system, single-lever height adjustment, rear bagger, mulch plug, side discharge chute.

FeatureDescription
Cutting Deck21-inch reinforced steel construction
EngineBriggs & Stratton 6.75 ft-lbs torque, 140cc
Cutting System3-in-1 (mulch, bag, side discharge)
Height AdjustmentSingle-lever, 6 positions (1.5-4 inches)
Drive SystemRear-wheel drive with traction control
Starting SystemEasy-start recoil mechanism
Fuel Tank0.5 gallon capacity
Wheels8-inch rear, 7-inch front
Weight65 lbs (unassembled)
Warranty2-year limited residential warranty

Assembly Instructions

Unpack and inspect all parts. Assembly requires basic tools (included).

  1. Attach handle: Align handle brackets with deck mounts, secure with provided bolts and wrench.
  2. Install wheels: Insert axle through wheel hubs, secure with washers and cotter pins.
  3. Attach grass bag: Connect bagger frame to rear deck hooks, ensure secure latch.
  4. Install mulch plug: Insert plug into rear discharge opening for mulch mode.
  5. Add engine oil: Fill with SAE 30 detergent oil (20 oz) before first use.
  6. Add gasoline: Use fresh unleaded gasoline (87 octane minimum).

WARNING! Always wear protective gloves during assembly. Keep hands clear of cutting blade.

First-Time Setup

Complete assembly, then prepare for first mowing operation.

  1. Check oil level: Ensure oil is at full mark on dipstick.
  2. Fuel check: Fill tank with fresh unleaded gasoline.
  3. Cutting height: Set single lever to desired height (recommend 3 inches for first mow).
  4. Cutting mode: Install mulch plug, bag, or side chute as needed.
  5. Safety check: Verify blade bolt is tight, all guards are in place.
  6. Start engine: Pull recoil starter slowly until resistance, then briskly.

CAUTION! Never operate without oil or with loose components. Clear mowing area of debris.

Specifications

Controls and Operation

Handle Controls: Drive control bar, height adjustment lever, engine control cable.

Operation Steps:

  1. Check area: Remove stones, toys, debris from lawn.
  2. Set height: Use single lever to choose cutting height.
  3. Start engine: Set throttle to FAST, pull recoil starter.
  4. Engage drive: Squeeze drive control bar against handle to move forward.
  5. Mowing pattern: Overlap each pass by 2-3 inches for even cut.
  6. Shut down: Release drive bar, move throttle to STOP, wait for blade to stop.

Safety Controls: Blade control lever must be engaged for blade rotation. Engine stops if released.

Cutting System Setup

Configure for mulch, bag, or side discharge operation.

  1. Mulching: Install mulch plug in rear discharge opening. Remove bagger.
  2. Bagging: Remove mulch plug, attach grass bag to rear hooks.
  3. Side Discharge: Remove mulch plug and bag, attach discharge chute to side port.
  4. Height Adjustment: Single lever controls all four wheels simultaneously.

Tip: For best mulching results, mow when grass is dry and not too tall.

Maintenance Procedures

Regular maintenance ensures optimal performance and longevity.

  1. After each use: Clean underside of deck, check for debris.
  2. Weekly: Check blade sharpness and balance, tighten bolts.
  3. Monthly: Check air filter, clean or replace as needed.
  4. Seasonally: Change engine oil, replace spark plug, sharpen blade.
  5. Annual: Drain fuel for storage, lubricate wheel bearings.

Blade Sharpening: Remove blade with wrench, sharpen at 30-degree angle, balance before reinstalling.

Storage Guidelines

Proper storage prevents damage and extends mower life.

  1. Drain fuel: Run engine until tank is empty, or add fuel stabilizer.
  2. Change oil: Replace with fresh SAE 30 oil before storage.
  3. Clean thoroughly: Remove grass clippings from deck, wheels, and engine.
  4. Protect blade: Coat with light oil to prevent rust.
  5. Store indoors: Keep in dry, covered area away from moisture.
  6. Battery maintenance: Not applicable (recoil start only).

CAUTION! Never store with gasoline in tank for more than 30 days without stabilizer.

Regulatory Information

EPA Phase 3 compliant emissions system. Meets ANSI B71.1 safety standards for walk-behind mowers. Copyright © 2025 Toro Company. All rights reserved. For genuine Toro parts and accessories, visit www.toro.com or contact 1-888-384-9939. Engine covered by Briggs & Stratton warranty.

Troubleshooting

SymptomPossible CauseCorrective Action
Engine won't startNo fuel, old gasoline, clogged filterAdd fresh fuel, check fuel line, clean air filter.
Poor cutting performanceDull blade, wet grass, low engine speedSharpen blade, mow when dry, set throttle to FAST.
Uneven cuttingUneven tire pressure, bent bladeCheck tire pressure, balance or replace blade.
Excessive vibrationLoose blade, damaged blade, debrisTighten blade bolt, replace damaged blade, clean deck.
Loss of powerDirty air filter, old oil, clogged deckClean/replace filter, change oil, clean underside.
Wheels not turningDrive cable adjustment, worn beltAdjust drive cable tension, replace drive belt.

Reset: For engine issues, allow to cool 5 minutes before restarting.

Service: 1-888-384-9939; www.toro.com

toro model 20037 manual © - All Rights Reserved 2025