My Lawn Mower
Chute Clogs

What We'll Cover

01. Chute Clogs

02. Grass-bag

03. Blade Wear

04. Tune-up

05. PTO

06. Belt Wear


My Lawn Mower
Chute Clogs

What We'll Cover

01. Chute Clogs

02. Grass-bag

03. Blade Wear

04. Tune-up

05. PTO

06. Belt Wear

Your Problem Will Likely Be Loose Battery Connections, Flat/Faulty Battery Or Faulty Starter Solenoid.

Causes

01. Poor Cutting Conditions

02. Deck Too Low

03. Dull/Damaged Blade

04. Deck Grass Build-up

05. Throttle Too Low

06. Poor Engine Performance 

07. Damage To Deck

08. Deck Belt Slip (Tractor) 

09. PTO Slip (Tractor)

10. Using Mulching Blade 

Most Common Cause

Grass height, weather conditions and a worn blade will be the most obvious reasons for the tractor or walk behind mower clogging.

 

Cutting wet grass, especially if it's long, will keep you busy clearing the chute. Lawn mower grass catcher troubleshooting is straight forward, most are common problems and easy to solve. 

 

Damp conditions, cutting too low, worn blade - all cause the chute to clog.

 

 

Chute Clogs

As a guide, you should cut no more than 1/3 off a blade of grass at once. For best results a mower shouldn't be cutting more than an inch of grass, and the best lawn height is about 3".  Cutting reguarly keeps the workload on the machine to a minimum and it's easier on your lawn.

 

Weather makes a big differance, obviously if the grass is damp the mower is going to struggle to perform. But I understand, sometimes it's nessaccery to cut wet grass when you need to get the job done.

 

A clogged chute can of course be a symptom of an underlying problem. So clearing the chute may not resolve the issue.

 

Grass build up or damage to the underside of the deck can cause the grass to catch and clog. The underside of the deck should be smooth so that the grass moves freely around the deck, up the chute and into the bag. 

 

 

 

Chute


mower grass chute

Clearing the chute may not solve the problem. Check the chute for damage or old dry grass build up.

Clean


mower deck

Old grass on the deck can cause problems. Regular cleaning will prevent build up and prolong the life of your mower.

mower chute

Chute

Clearing the chute may not solve the problem. Check the chute for damage or old dry grass build up.

Clean

Old grass on the deck can cause problems.

Regular cleaning will prevent build up and prolong the life of your mower.


mower deck

Deck Wash Port

Clean the underside of the deck at the end of the season, as the acid in the grass eats away at the metal over the winter. Most mowers will have a garden hose connection on the deck, simply connect your hose and run your blades to clean the underside of the deck. This does a reasonable job at cleaning.

 

 

 

 

Clean


mower deck

The was out port isn't fitted to all mowers. It does a pretty good job of cleaning the underside of the deck.

Hose


mower deck

Move your mower to a suitable location as it leaves a bit of a mess.

Just attach and turn on garden hose. Start your mower to engane blades. 

Run until water runs clear - simple!

mower wash port

Clean

The was out port isn't fitted to all mowers.

It does a pretty good job of cleaning the underside of the deck.

Hose

Move your mower to a suitable location as it leaves a bit of a mess.

Just attach and turn on garden hose. Start your mower to engane blades. 

Run until water runs clear - simple!


Battery Connections

Elbow Grease

The alternative is to lift the front of the tractor and get in their with a stiff brush. A liberal coat of WD40 will help protect over the winter and aid in keeping the deck grass free in the spring.

 

 

 

 

mower deck clean

Clean

Lift the front of your tractor, secure it well before climbing under.

A wire brush and paint scraper does the job.

Protect

To help prevent clogging:

Option 1 - Quick fix is spray the deck with WD40, it does help but it won't last. 

Option 2 - Spray deck with DuPont Teflon coating.

Option 3 - Spray the the deck with bed liner, my prefared option. works on tractors, riders and walk behind mowers.


Mower deck Mower deck

Clean


mower grass chute

Lift the front of your tractor, secure it well before climbing under.

A wire brush and paint scraper does the job.

Protect


mower deck mower deck

To help prevent clogging:

Option 1 - Quick fix is spray the deck with WD40, it does help but it won't last. 

Option 2 - Spray deck with Dupoint Teflon coating.

Option 3 - Spray the the deck with bed liner, my prefared option. works on tractors, riders and walk behind mowers.

Grassbag

A clogged grass bag is a common problem. Tractors and walk behind mowers often get cleaned at the end of the season (well some do) but bags rarely do. Symptoms of a clogged bag are not collecting or only a half filled grass bag.

 

Examine your bag/box, when held to the light you should be able to see through it. A stiff brush will remove the old grass or use a power washer.

 

Consider buying a new grass bag if damaged. They are available to purchase usually with or without the frame. Check if the bag/box sits correctly against the mower body. If it's loose, the air and grass flow to the bag will leak.

 

 

Bag


grassbag

Thatched grass on the inside of the bag is a common issue.

It prevents air flow through the bag which in turn prevents grass from entering the bag.

Clean


riding mower battery test

As a rough guide you should be able to see through the bag.

A stiff brush or better a pressure washer does a great job.

mower grass bag

Bag

Thatched grass on the inside of the bag is a common issue.

It prevents air flow through the bag which in turn prevents grass from entering the bag.

Clean

As a rough guide you should be able to see through the bag.

A stiff brush or better a pressure washer does a great job.


Ride-on mower battery test

Blade Damage

Two types of blades are common, the lift blade and mulching blade. They are fitted to tractors, ride-ons and walk behind mowers. A defective blade can cause vibration, uneven cutting and poor grass collection. No need to tell you a bent blade is dangerous and should never be repaired. A new blade, bolt and washer is the way to go. 

 

 

Examine your blades checking for damage, misalignment, bent or broken tips. Your blade is the business end of the mower and needs to be in top condition.

 

 

 

Timed Blades

Some deck set ups will have an overlapping cut, although more common on lawn tractors than walk behind mowers. Toro timemaster walkbehind mower has a timed blade set up.

 

To achieve this the blades must be fixed at a set angle in relation to each other. This is done by using a toothed timed belt. If one of the blades hits an object, the blades can go out of time or the belt can break.

 

This leaves the blades free to hit and damage each other, blade damage is common on timed decks. Check out "Timed deck belt replacing".

 

 

Worn Blade

A worn blade will cause clogging, as the carefully engineered blade wears, the trailing edge is less efficient at moving the clippings. The leading edge will also be worn from grit and debris, and sharpening sessions will likely have changed its shape.

 

The average mower should get a new blade every 2nd or 3rd season.

 

 

 

 

 

Ride-on mower engine Ride-on mower engine Ride-on mower engine

Damaged

Defective blades can cause vibration, uneven cutting and poor grass collection.

Examine your blades carefully, checking for damage, misalignment, bent or broken leading and trailing edges.

A mowing blade may look OK, but they do wear.

Mowing blades are engineered to cut and move grass, as they wear they become much less efficient.

A worn blade will cause clogging.

Damage


mower blade mower blade mower blade

Defective blades can cause vibration, uneven cutting and poor grass collection.

Examine your blades carefully, checking for damage, misalignment, bent or broken leading and trailing edges.

A mowing blade may look OK, but they do wear.

Mowing blades are  engineered to cut and move grass, as they wear they become much less efficient.

A worn blade will cause clogging.

Lift Blade

The Lift blade also known as the 2 in 1, so called because it baggs and discharges. Lift blades vacuum the grass up right, before cutting and moving the clippings to the bag. Lift blades are specially designed for collecting grass and come in low, medium and high lift.

 

Lift meaning sucking power, a higher lift blade will require a more powerful engine. The lift is created by the curving upwards of the trailing edge of the blade.

 

 

 

 

2 in 1

If you like bagging - You need a lift blade.


mower blades

2 in 1


mower blade

If you like bagging - You need a lift blade.

Mulching Blade

A true Mulching blade is designed to cut grass, circulate it around the deck cutting it several more times and dropping it back onto lawn as fine clippings.

 

Youll know a mulching blade when you see it, the leading edge isn't straight, it curves up and down. This causes the grass blades to be cut several times at differant heights -  resulting in fine clippings.

 

A true Mulching blade is not designed to collect.

 

That got engineers thinking - Meet the hybrid mulching blade or 3 in 1. It attempts to do it all, mulch, baggs, discharges, however we all know it can't be excelant at everything, and it isn't.

 

My advice, if your not interested in mulching then fit a lift blade. It will always bag better than any hybrid mulching blade.

 

 

 

 

 

 

3 in 1

Mulching has become quite popular, and manufacturers have responded by making a blade that try's to do it all, but doesn't quite succeed.


mower starter solenoid

3 in 1


riding mower engine

Mulching has become quite popular, and manufacturers have responded by making a blade that try's to do it all, but doesn't quite succeed.

Engine Performance

Its also worth considering, is the throttle set correctly, it should be set to fast/run when cutting. Is the engine running as it should. If the engine power is reduced the mower may still cut well, but will be less efficient at collecting. A small engine tractor or walk behind mower should have a tune-up at the beginning of every season, regardless of how well it might be running.

 

Check out:

"Lawn tractor tune-up"

"Lawn mower tune-up"

 

 

 

 

 

Bad Gas

Old fuel is the number one cause of poor engine performance, use a gas stabilizer over the winter to help protect your lawn tractor carburetor.

 

Check out:

"Lawn mower carburetor cleaning"

"Lawn tractor carburetor cleaning" 

 

 

Tune-up


mower

Mowers like a tune-up at least once per season.

tractor mower

Tune-up

Mowers like a tune-up at least once per season.

Power Take Off (PTO)

  • The PTO clutch assembly will not be fitted to all mowers, and so this may not be applicable. It's fitted mostly to tractors, ride-ons and larger walk behind mowers. The PTO clutch is a unit fitted to the end of the crankshaft. The deck belt wraps around the PTO pulley, its function is to apply the power of the engine to the blades when a switch or lever is operated.  
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PTO Wear

  • The PTO clutch when worn, will slip reducing power to the blades. This will be especially noticeable in taller grass. The PTO if fitted will be manual or electromagnetic. If manual it will likely have a lever and cable to operate - check that the cable is pulling the PTO. Both types can't be repaired, they must be replaced.
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PTO

Check the PTO system. The manual version is engaged by a cable. It lives on the crankshaft, right under the engine.

Check that the cable is pulling the pto lever all the way.


Ride-on PTO
mower PTO

Fitting

Replacing the PTO isn't difficult, but air tools would make it really easy.

PTO


MOWER PTO Riding mower PTO

Check the PTO system. The manual version is engaged by a cable. It lives on the crankshaft, right under the engine.

Check that the cable is pulling the pto lever all the way.

Tractor Belt Wear

  • Belt wear is also a common reason for a chute to clog, check the deck cutting belt for damage and general wear & tear. A new belt will transfer more of the engine power to the cutting blades and will improve the cutting and bag filling performance. Belt types and lengths will be specific. Some brands will only work well using Oem (Original Equipment Manufacturer) belts. 
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Cutting Belt 


MOWER PTO Riding mower belt

A cutting deck belt that's slipping will be less efficient at collecting.

Check the belt for proper tension, cracking, glazing or contamination.

Damaged belts will cause vibration and poor general performance. A typical deck belt might last 3 - 4 years.

mower deck belt

Worn

A cutting deck belt that's slipping will be less efficient at collecting.

Check the belt for proper tension, cracking, glazing or contamination.

Damaged

Damaged belts will cause vibration and poor general performance.

A typical deck belt might last 3 - 4 years.


Mower deck belt