toro lawnmower how to and troubleshooting guide
Tips & Tricks

Toro Lawnmower Troubleshooting & How To Guide

Toro lawn mowers are available in different types, like walk-behind, self-propelled, push, gas, and electric models. While Toro machines are of superior quality when compared to some other brands, being machines, they too have issues. The good thing with these mowers is a lot of the problems are just minor challenges that can easily be fixed by performing basic troubleshooting procedures. If you are having issues with your Toro lawn mower or need help operating the machine, here is a simple guide with troubleshooting instructions for commonly reported issues that you can use.

Why is My Toro Lawn Mower Not Starting?

If your Mower is not starting, it could be because of the following reasons:

The filter is dirty

When the filter is dirty, it makes it more difficult for the engine to draw in air. Check the filter to see if it is dirty, and if so, clean or replace the filter.

Spark plug is old or faulty

It is easier to start the mower when the spark plug is in good condition. If you have an old spark plug or suspect it is faulty replace it with a new one that can be able to provide a better spark to ignite the fuel-air mix within the engine. Also, make sure the spark plug wire is properly attached to the spark plug.

Old fuel

If you are using old fuel (more than 30 days), it may also be the reason you are having difficulties starting your mower. Verify the fuel you are using was purchased within the last 30 days. Additionally, check to make sure there is no dirt, water, or stale fuel in the tank that might clog the fuel pump.

Battery doesn’t have sufficient charge/ fuse is blown out

On electric start models, the battery needs to be charged at the start and end of the season before storing the mower behind a closed weatherproof door. One charge may be sufficient to last the entire season. If not, additional charging during the season may be necessary. Also important to note is that you cannot start your mower with the electric start or charge the battery unless you install the fuse.

How Do I Clean the Carburetor on My Toro Lawn Mower?

Cleaning the carburetor in a Toro lawn mower will help keep the engine in good working condition. There are small holes in a carburetor that air and fuel must pass through. If these are clogged or obstructed, the carburetor will prevent the engine from working. Cleaning the carburetor will help keep these openings free and also remove any dirt or grass clippings build-up.

To clean the carburetor of the 6.5 HP Tecumseh engine in a Toro lawn mower, follow these steps:

  1. Remove the spark plug from the spark wire and set it aside. Set the brake on the lawn mower.
  2. Unscrew the four 1/4-inch bolts holding the case on top of the Toro mower. Pull the oil dipstick up, lift off the cover of the mower and then replace the oil dipstick.
  3. Hold the gas tank, pull back and lift it up. Place pliers on the fuel clip beneath the tank and pull firmly to remove it.
  4. Remove the 7/16-inch bolts attaching the muffler to the lawn mower and then remove the bolts holding the carburetor to the lawn mower. Remove the bolt attaching the carburetor to the hose.
  5. Remove the metal linkages from their connections on the mower. Use a piece of tape and a number to mark each linkage so you can remember where to re-attach them later. Pull the carburetor from the mower.
  6. Place a wrench on the bolt on top of the carburetor and remove the bolt. Pull up the cup that was being held by the bolt, and then pull the pin that latches the pieces together. Pull the float and the needle off once you are done.
  7. Spray carburetor cleaner down the hole you exposed. Use a dry rag to clean the external parts of the carburetor and use the carburetor cleaner to remove grime and fuel. The let the parts to dry.
  8. Spray cleaner through the bolt you removed from the carburetor to remove build up.
  9. Replace the parts and then put the carburetor back on the mower, making sure all the linkages you had removed are in the right places. Replace the muffler and gas tank. Remove the oil dipstick, place the cover back on the mower and then replace the oil dipstick. Then screw the cover back on the Toro mower.

Why is My Toro Lawn Mower Surging?

Surging is caused by a weak air-fuel ratio. This can be due to a lack or fuel because of a blockage or excess air when there is a leak at the manifold.

To troubleshoot this problem, clean and remove any obstructions that may be present. You can start at either the carburetor or the fuel tank.

How to Start a Toro Lawn Mower without Primer

The primer on your lawnmower works by squirting fuel into your engine. It is the easiest way to use a lawnmower. However, in some unfortunate cases, the primer bulb may get damaged or stop working. The good news is that there are alternative methods to start your mower without the primer.

To start a Toro lawn mower without the primer, follow these steps:

  1. Find the air cleaner which is located near the engine and remove the cover. The cover may be clipped on or screwed in.
  2. Proceed to remove the air cleaner itself. As you do, take note of its location.
  3. The housing should be clearly exposed by now. Take the starter fluid and spray some of it in the hole that you see in the housing.
  4. Then quickly put the air cleaner back in its original position and replace the cover. You need to be quick since the starter fluid tends to evaporate when exposed to air.

Toro Lawn Mower Won’t Start After Sitting

If you are having trouble getting your Toro mower that has been sitting to start, the following are troubleshooting tips you can try to resolve the problem:

Check and change the oil

It is always a good idea to check the oil if the lawnmower has been sitting for a while. Check that the oil is good quality, doesn’t have residue in it, and the amount is sufficient. If not, you need to change the oil to be able to start the mower.

Check the gas tank

Check to make sure you have gas in the tank and that it is not more than 30 days old. If the gas is more than 30 days old then you will need to empty the tank and put in fresh gas. You may dump the tank by tipping the mower or siphoning the gas out.

Any internal combustion engine operated equipment, be it an air compressor, a golf cart, or weed wacker needs fuel inspection before running it for the faster time in a very long time

Change the air filters

After you are through with the gas tank and changing the oil, check the mower’s air filter as these can get clogged. If the air filter is dirty, it may prevent the mower from starting since will be making it difficult for the engine to draw air that is required for combustion.

Replace the spark plug

It is easy to locate the spark plug in your mower since it has a wire that attaches to it. Make sure the wire is in good shape and that there is a good connection there. Then, check the spark plug itself. You can remove the spark plug using a socket wrench.  Check for corrosion or discoloration on the spark plug as these indicate it may be old or even faulty. If in doubt, just replace the spark plug.

Clean the carburetor

Another possible cause for your lawn mower not starting after sitting is because the carb is corroded or it has clogged if the fuel was left in the engine and left to evaporate leaving behind a sticky residue inside the carburetor.

Clean the carburetor to clear clogging and obstructions that prevent the engine from working properly.

Toro Lawn Mower Won’t Self Propel

There are several possible reasons why a mower fails to self-propel. Identifying the cause of the problem is the first step to fixing the issue:

Belt problems

When you have a loss of drive on your self-propelled Toro mower, the first place you should be the belt. These types of mowers rely on a belt to turn the wheels. If the belt is worn and slips, stretched with time, torn, or is broken and completely off the machine, the mower will have issues self-propelling.

Inspect the belt and look for missing chunks of rubber or variation in the width of the belt along its length. Replace the belt if it looks damaged.

Drive cable issues

A problem with the drive cable can cause the wheels to malfunction since the mower depends on the self-propel drive cable to control it.

If the drive cable is the problem, follow these troubleshooting steps to fix the issue:

  • Loosen the cable support nut that is located on the side of the mower’s handle.
  • Pull the cable’s jacket toward the engine until the cable is taut and displays no slack.
  • Tighten the cable support nut back into position to hold the adjustment you have made.
  • Excessive debris accumulation

Mowers accumulate debris on the underside of the deck and around the wheels.  If the mower has not been cleaned for a long time this problem can be worse.

Check the wheels and the belt to make sure that debris is not the cause of the front-wheel-drive problem. Also, disconnect the spark plug, turn the mower over and clean out grass clippings, twigs, or rocks that may be lodged in the wheels and belt system.

Improper mower operation

Operator error could also be the reason your mower fails to self-propel. Self-propel mowers have two separate bars on the handle. The blade-control bar, which must be held in place when pulling the starter coil handle to start the machine. There is also the self-propel bar, located underneath the handle, which you should squeeze once the mower’s engine is running.

To disengage the front-wheel drive, simply release the self-propel drive. To stop the blades and shut the engine, release the blade control bar.

Why is My Toro Lawn Mower Smoking?

Your lawnmower can emit smoke for several reasons of which you can tell from the color of the smoke:

Black Smoke

Black smoke may indicate that the mower is “running rich” or burning too much gasoline. Your mower’s carburetor regulates the gas to air mixture ratio. If there isn’t enough air going to the carburetor, the mixture has a higher gasoline percentage, which can create black exhaust smoke.

If your mower has black smoke, this may be due to a dirty or clogged air filter that prevents sufficient airflow to the carburetor.  To fix this problem, clean the filter or replace it.

White or Blue Smoke

White or blue smoke may indicate an oil spill on the engine.  This may have happened if you recently changed the oil or you were mowing on a slope greater than 15 degrees. It could also have happed if you tipped the mower on its side.

If your mower has white or blue smoke, restarting the mower and allowing the spilled oil to burn off may help fix the issue.

Toro Electric Mower Battery Troubleshooting

Mower won’t start

On electric start models, the battery needs to be charged at the start and end of the season. One charge may be sufficient to last the entire season. If not, additional charging during the season may be necessary. Also important to note is that you cannot start your mower with the electric start or charge the battery unless you install the fuse.

  • Toro lawn mower battery keeps dying
  • Check the battery. One or more cells in the battery may be dead. Try charging the battery with a battery charger. If the battery still won’t hold a charge, the battery is defective and will need to be replaced.
  • The alternator could be defective. To determine this, use a multimeter to test the alternator  voltage output according to the wiring diagram.
  • The charger could be defective. To determine this, use a multimeter to test the charger for proper voltage output. In addition, test the outlet used by the charger, and ensure that the outlet has not tripped a breaker.
  • Check the voltage regulator. If voltage regulator is defective, the battery won’t receive enough voltage, causing the battery to drain quickly.

How to Test the Motor on a Toro Electric Mower (Battery powered models)

To test the motor in a Toro battery-powered model follow these steps:

  1. Unplug the motor from the wire harness.
  2. Set an ohmmeter on Rx1 and zero the meter.
  3. Attach one test probe to each of the wires going to the motor and note the reading. Slowly rotate the armature of the motor and watch the tester. The needle should move a little, but at no time should it go to the extreme ends of the scale. There should be some resistance there at all times.
  4. If the needle goes to infinity (denoted by something looking like an 8 on its side) a wire inside is broken or the brushes are not contacting the armature. If you find a broken wire accessible and can splice it, do so. If the broken area cannot be spliced, the motor must be replaced.

How to Replace the Transformer on Toro Electric Mower

To replace the transformer on a Toro electric mower (battery models), follow these steps:

  1. Remove the hood and disconnect the battery cables.
  2. Lift the charger assembly from its slot. Below the charger are four wires which plug into the charger terminals through slots in the body. Unplug these four wires. Tag the wires if necessary to remember which wire goes where.
  3. Remove the nut holding the solenoid mounting bracket to the motor mounting screw.
  4. Turn the mower on its side and remove the blade, bushing, fan, and spacer.
  5. Remove the 4 screws holding the motor to the chassis. Be ready to catch the motor and set it aside.
  6. Remove the 11 screws holding the liner to the chassis. Lift the liner off. The transformer is between the rear wheels inside a plastic housing. Note the transformer orientation when it is removed.
  7. Replace the transformer in the housing and replace the housing in the chassis. Make sure the transformer terminals are in the correct slots.
  8. Reinstall the liner, blade, fan and other parts you had removed.

How to Replace the Blade on Your Toro Lawn Mower (Toro walk behind lawn mower)

Before replacing or repairing anything on your Toro mower, please follow these safety precautions: shut the lawn mower engine off and allow it to cool, disconnect the spark plug wire to prevent accidental starting, and tuck it away so that it doesn’t make contact with the spark plug.

To replace a Toro walk behind lawn mower blade, you will need the following:

  • Replacement blade (Toro Parts Blade 131-4547-03)
  • Breaker bar
  • Scraper
  • Torque wrench
  • A piece of wood

Then follow these instructions:

  1. Tip the mower over but keep the air filter side up to prevent the oil from going into the air filter and carburetor as this will prevent the mower from running when you tip it back over.
  2. Wedge your piece of wood between the mowing deck and the blade itself to stop the mowing blade while you loosen and remove the bolt off the bottom of the blade. With the piece of wood firmly in position, connect the breaker bar and 16 mm socket, place them on the bolt and twist to loosen.
  3. Once the bolt begins to loosen, remove the piece of wood. Set aside the breaker bar and socket, and continue twisting the bolt loose using your hand.
  4. After removing the bolt, inspect it for galling and to make sure the bolt has not been stripped out. If the bolt is worn out or damaged, you will need to replace it before putting it back on the mower.
  5. With the bolt removed, now remove the blade adapter and the blade itself from the mower. Scrape out any kind of debris from the mowing deck that can prevent the mower from recycling correctly. Install the new blade once the deck is clear.
  6. Insert the new blade with the wing side of the blade up towards the moving deck as this is what gives the blade its lift to lift the grass. The reinstall the blade adapter and bolt. Use your hand to tighten the bolt and it is finger tight and prepare to use the torque wrench to torque the blade back down.
  7. Place the piece of wood between the blade and mowing deck once more, to block the blade so that you are able to torque it down. Toro recommends 60 foot pounds on this mower to properly torque down the blade bolt. So set the torque wrench to 60 ft pounds and then torque down the bolt until the torque wrench clicks.
  8. Remove the piece of wood and tip your mower back on its wheels. Reinstall the spark plug wire, then start the mower and check for proper operation.

Toro Lawn Mower Filter Replacement Guide

Gently tapping your mower’s air filter on a hard surface helps loosen debris and is one way to troubleshoot a dirty air filter. But, if the air filter is excessively dirty, you need to replace it with a new filter.

Follow these steps to replace the air filter:

  1. Unclip the top of the air-filter cover.
  2. Remove the air filter.
  3. Install the new air filter.
  4. Use the clip to install the air-filter cover.

For the in-line fuel filter, it is recommended you replace it every 200 hours. Follow the steps below to replace the in-line fuel filter your Toro Riding mower:

  1. Park the machine on a level surface and disengage the blade-control switch.
  2. Move the motion-control levers outward to the PARK position, shut off the engine, remove the key, and wait for all moving parts stop before leaving the operating position.
  3. Replace the in-line filter.

Toro Riding Lawn Mower Troubleshooting Guide

Troubleshooting your Toro Lawnmower can help identify and fix issues it may have. Follow the steps below to troubleshoot:

  1. Park the mower on a flat level surface, and engage the parking brake. Start the engine. If the engine won’t start, make sure the PTO is disengaged all the way and that the parking brake is engaged and the operator is sitting in the correct position on the seat. Check to make sure the Toro safety interlock components are in the correct position by referring to your user manual.
  2. Check that the battery was installed with the negative terminal attached to black ground wire, and the positive terminal attached to the red wire. Check battery water level, then charge the battery until it is fully charged with an automotive battery. Remove the battery cables from the battery terminals and clean the terminals with a wire brush to get rid of corrosion. Re-attach the battery cables.
  3. Tighten the engine ground wire running from engine to the frame. Check for loose wiring connections in the fuse box and wire harness, and make sure all loose connections are tighten. Verify that all fuses are good (not burnt or blown).
  4. Replace gas in the fuel tank with fresh gas. Clean the fuel filter and check for adequate flow from the fuel lines. Clean or replace the air filter. Clean or replace the spark plug, ensuring the spark plug gap is set correctly. Make sure the spark plug wire is attached firmly to the spark plug.
  5. Start the engine. If it runs rough or smokes excessively after a 5-minute warm up period the engine needs a tune up. If the mower only runs rough when in the mowing configuration, then you need to adjust the PTO belts and mowing decks.

How to Turn Off Toro Lawn Mower

You can turn off your Toro lawn mower by shutting off the engine. To do so, follow the instructions below:

  • Release the blade-control bar.
  • The engine should shut off and the blade should stop within 3 seconds when you release the blade-control bar.

To turn off a Toro riding mower:

  • Disengage the blades by moving the blade-control switch to the OFF position.
  • Move the throttle lever to the FAST position.
  • Turn the ignition key to the OFF position and remove the key.