Yard-Man 979 User Manual (English)

Questions and Answers:

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Ryan CoffeyAug 14, 2025
Why won't my Yard-Man 979 Lawn Mower start?
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  baileytimothyAug 14, 2025
  Your Yard-Man Lawn Mower might not start for several reasons. First, ensure the blade control handle is engaged. Check that the spark plug wire is connected. If the fuel tank is empty or contains stale fuel, refill it with fresh gasoline. A blocked fuel line could also be the issue, so try cleaning it. Inspect the spark plug; clean, adjust the gap, or replace it if necessary. Lastly, if the engine is flooded, wait a few minutes before attempting to start it again.
C
Casey PowellAug 17, 2025
What to do if my Yard-Man 979 engine runs erratically?
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  Mr. Charles BurtonAug 17, 2025
  If your Yard-Man Lawn Mower engine is running erratically, start by checking the spark plug wire to ensure it is securely connected and tightened. A blocked fuel line or stale fuel could also be the culprit; clean the fuel line and refill the tank with fresh gasoline. Make sure the vent in the gas cap isn't plugged. Additionally, check for water or dirt in the fuel system by draining the tank and refilling with fresh fuel. A dirty air cleaner can also cause this issue, so clean it. Finally, the carburetor might need adjustment.
D
Dana RossAug 20, 2025
How to fix a Yard-Man 979 that idles poorly?
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  Danielle BeckAug 21, 2025
  If your Yard-Man Lawn Mower idles poorly, several factors could be responsible. Start by checking the spark plug for fouling, damage, or an incorrect gap; reset the gap to .030” or replace the spark plug if needed. The carburetor might also be improperly adjusted. Another potential cause is a dirty air cleaner, so try cleaning it.
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Robert DavisAug 25, 2025
Why is my Yard-Man Lawn Mower engine overheating?
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  andrea90Aug 25, 2025
  If your Yard-Man Lawn Mower engine is overheating, there are a few potential causes. Begin by checking the engine oil level and fill the crankcase with the proper oil if it's low. Also, ensure that airflow is not restricted by removing the blower housing and cleaning any debris. Finally, the carburetor may not be adjusted properly, so consider adjusting it.
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adampattersonAug 27, 2025
Why does my Yard-Man Lawn Mower have excessive vibration?
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  mary71Aug 27, 2025
  Excessive vibration in your Yard-Man Lawn Mower can stem from a couple of issues. First, check if the cutting blade is loose or unbalanced; tighten the blade and adapter and balance the blade. Alternatively, the cutting blade might be bent, in which case you should replace it.
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Veronica AllenAug 30, 2025
What to do if my Yard-Man 979 won't mulch grass?
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  michaelwrightAug 30, 2025
  If your Yard-Man Lawn Mower isn't mulching grass effectively, consider these points. Avoid mowing when the grass is wet; wait for it to dry. If the grass is excessively high, mow once at a high cutting height, then mow again at the desired height, or make a narrower cutting path. Also, a dull blade can hinder mulching, so sharpen or replace the blade.
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Nancy PittmanSep 3, 2025
How to fix an uneven cut with my Yard-Man Lawn Mower?
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  macdonaldbeckySep 3, 2025
  To correct an uneven cut with your Yard-Man Lawn Mower, first ensure that all four wheels are in the same height position. Also, check the blade; a dull blade can cause an uneven cut, so sharpen or replace it.
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Leah GrahamSep 6, 2025
Why are the wheels not propelling on my Yard-Man 979?
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  Amanda GuerreroSep 6, 2025
  If the wheels on your Yard-Man Lawn Mower are not propelling, there are a couple of things to inspect. First, check the belt to ensure it is properly installed on the pulley and moving correctly. Also, debris might be clogging the drive operation; clean out any debris with the engine off.
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Laura TaylorSep 9, 2025
Why does my Yard-Man 979 Lawn Mower occasionally skip at high speed?
- N
  Natalie HudsonSep 10, 2025
  If your Yard-Man Lawn Mower occasionally skips or hesitates at high speed, it could be due to the spark plug gap being too close. Adjust the gap to .030” to resolve this issue.

Yard-Man 979 Specifications

General

Engine Displacement	190cc
Cutting Height Range	1.25 - 3.75 inches
Deck Material	Steel
Grass Collection	Rear bag
Starting System	Recoil
Engine	Briggs & Stratton
Engine Type	4-cycle
Drive System	Rear-wheel drive

Summary

Important Safe Operation Practices

General Operation Safety

Read manual, use caution, never allow children under 14, inspect area, wear safety gear.

Safe Slope Operation

Mow across slopes, avoid steep inclines (>15 degrees), don't mow wet grass.

Child Safety Precautions

Keep children away, be alert, turn off mower if child enters area.

Safe Gasoline Handling and Service

Handle gasoline carefully, refuel outdoors, use approved containers, keep mower clean.

Slope Gauge

Using the Slope Gauge

Guide to determine slopes where mower operation is unsafe, avoid >15 degrees.

Assembling Your Lawn Mower

Unpacking and Carton Removal

Steps for unpacking the mower from its shipping carton.

Handle Assembly and Setup

Instructions for raising and securing the handle assembly.

Spark Plug Wire Disconnection

Procedure to disconnect the spark plug wire before setup.

Know Your Lawn Mower

Starting and Engine Controls

Location and operation of recoil starter and engine controls.

Blade and Drive Controls

Function of blade control handle and drive clutch control.

Adjustment Levers

Location and purpose of cutting height and shift levers.

Stopping the Engine

Procedures for safely stopping the engine and blade.

Operating Your Lawn Mower

Fueling and Oil Check

Instructions for filling the fuel tank and checking engine oil level.

Starting Engine Procedure

Steps for priming, connecting spark plug wire, and starting the engine.

Safe Mowing Practices

Clearing the lawn, avoiding wet grass, and proper mowing techniques.

Mulching Guidelines

Tips for effective mulching, avoiding wet or tall grass.

Attaching Grass Bag and Chute

Steps to attach the grass bag adapter, bag, and side discharge chute.

Emptying the Grass Bag

How to remove and empty the grass bag.

Making Adjustments

Cutting Height Adjustment

How to adjust the cutting height using the lever.

Handle Height Adjustment

Steps to adjust the handle to a different height position.

Drive Clutch Control Adjustment

Adjusting the drive clutch control for proper engagement.

Shift Lever Cable Adjustment

Adjusting the shift lever cable for smooth speed changes.

Maintaining Your Lawn Mower

Maintenance Schedule and Responsibilities

Overview of maintenance tasks and customer responsibilities.

Lubrication Points

Lubrication for blade control, wheels, and engine.

Deck Cleaning

Procedures for cleaning the underside of the mower deck.

Blade Care and Replacement

Procedures for blade removal, sharpening, and replacement.

Drive Belt Maintenance

Steps for drive belt removal, replacement, and installation.

Preparing for Storage

Steps to prepare the mower for long-term storage.

Troubleshooting

Engine Starting and Running Issues

Diagnosing and resolving problems with engine start-up and operation.

Mower Performance Problems

Addressing issues like vibration, cut quality, and mulching.

Drive System Troubleshooting

Resolving problems with the mower's drive or wheel propulsion.

Manufacturer's Limited Warranty

Warranty Coverage and Exclusions

Details on what is covered, limitations, and what voids the warranty.

Obtaining Service and Support

How to get warranty service through authorized dealers or customer support.

Legal Rights and State Law

Information on how state laws relate to the limited warranty.

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