SCAG Zero Turn Mower Spins But Doesn’t Start!

When there isn’t enough oxygen, fuel, or a spark to start the combustion process, the engine will spin over but won’t start in a SCAG zero-turn mower.

The choke may be set too high, the air filter may be clogged, the fuel filter may be plugged, the fuel pump may be broken, the carburetor may be unclean, the spark plug may be damaged, or the fuel may be old.

Observe all of the security measures outlined in the SCAG’s user guide at all times. Before attempting any repairs, make sure the engine has cooled down completely and the key and spark plug wires have been removed.

9 Explanations As to Why Your SCAG Zero-Turn Mower Isn’t Starting

A SCAG Lawnmower With a Stuck Choke or an Incorrectly Set Choke

When activated, the choke limits the flow of air to the motor. This is essential for getting a cold engine moving.

In order to start a cold engine, you need to use a higher gas concentration and less air. The choke lever needs to be moved to the off position once the engine has warmed up to allow it to receive more air and keep running.

The choke must be disengaged before starting a warm engine.

FIX: If the choke lever isn’t set properly, your SCAG may not run at all. When starting a cold engine, the choke must be closed, whereas starting a heated engine it must be open.

Ensure the choke plate is not blocked and the choke cable can move freely if the airflow is still problematic after adjusting the choke. In order to unstick the choke plate and the links, you should use carburetor cleaner.

If the cable appears to be stretched or worn, a new SCAG choke cable should be installed.

Blockage in the SCAG Lawnmower’s Air Filter

The air filter is another potential source of airflow restriction that would prevent your SCAG from beginning once it has turned over. The engine could be severely damaged by allowing dirt and debris to be sucked into the air intake without this filter.

It is imperative that the air filter be checked frequently. If you want to maintain its good shape, you’ll need to cleanse it or replace it. In extreme cases, a clogged air filter can impede sufficient airflow.

Start each mowing season with a cleanse air filter and replace it as needed. Before you start up your SCAG, make sure the air filter has been checked and is in good working order.

FIX: If your engine employs a pre-cleaner, you can solve this problem by following the steps below to cleanse the SCAG paper air filter and the foam pre-cleaner.

If you own a SCAG mower and are not sure what kind of filter it uses or how to cleanse it, consult your operator’s manual.

More about it: Lawn Mower Air Filters: Difference & How to Cleanse Them.

Cleanse a SCAG Mower Paper Air Filter

• Take off the air filter from the housing. Do your best to prevent any dust or other debris from entering the air intake.
• To remove any remaining dust or debris from the air filter housing, use a clean, dry towel.
• To eliminate as much dust as possible from a paper air filter, tap it against a hard surface.
• You can test the transparency of your paper filter by holding it up to a light and seeing the effect.
• When light is no longer a problem, you can reuse the filter.
• In cases where no light is coming through, the filter is too dirty, or it has been broken, a new filter should be installed.
• Attach the air filter cover back into place. (If your mower has a foam pre-filter, follow the cleaning and installation steps below before securing the filter cover).

Cleanse a SCAG Mower Foam Pre-Filter (When put to use on a lawnmower. The pre-filters used by various engines vary)

It is not to be confused with the primary foam filter. To further improve the efficiency of a paper air filter, many people add a foam pre-filter first. The paper filter will be ruined if oil is ever added to the pre-filter.

• It’s time to check the pre-filter. If you detect any tears or if it has gotten brittle, throw it away and get a new one.
• In order to get rid of grime and grease, easily wash the foam filter in warm water with a drop or two of mild dish soap.
• Water should be used to eliminate all traces of soap and allow the water to drain freely.
• Spread out flat and let air dry. The filter can dry more quickly if you put it in the sun.
• Reconnect the filter cover and combine the paper primary filter with the foam pre-filter after it has dried.

A SCAG Mower with a Grimy Spark Plug

The spark plugs should next be inspected. Use a 3/4-inch or 5/8-inch socket wrench to take out the plug. What you need to know is what kind of engine you have before you can determine the right size.

If the spark plug is filthy or broken, the engine may not start. Inability to start and operate the engine is directly related to the lack of a spark plug.

Any spark plug with a blackened tip, a charred electrode, or cracked porcelain should be replaced immediately. New spark plugs should be installed if any of these problems are discovered.

FIX: A plug that is otherwise functional but slightly unclean may be cleaned using this method. To get rid of the carbon accumulation, you might use a little wire brush.

After checking that the space between the electrodes is appropriate, replace the spark plug. The spark plug wire must then be attached tightly.

New spark plugs should be installed in your SCAG mower at the start of each season since they are crucial to the mower’s performance.

A SCAG Mower Running on Old Gas

It’s probably common knowledge, but gas loses its quality with time. Indeed, it will start to fall apart within 30 days after purchasing.

The varnishes and sticky deposits left behind by old gas reduce fuel flow and shorten the life of parts.

Always buy new gasoline and use it up within 30 days to make sure your SCAG mower is getting the appropriate fuel. Don’t use ethanol-rich gas.

Gasoline with an octane value of 87 or above and less than 10% ethanol should be used. Gasoline powers SCAG mowers with 4-cycle engines. Mowers with two-cycle SCAG engines run on a combination of gas and oil.

To learn more about how to determine whether your engine requires 2-cycle or 4-cycle fuel, see visit SCAG lawn mowers use this kind of gas.

FIX: If you discover that your SCAG’s fuel tank contains stale gas, you should drain the tank with a gasoline siphon pump.

For cleaner gasoline and less moisture in the fuel system, fill your tank with new gas and add a fuel stabilizer, such as Sea Foam. Learn more about Sea Foam’s advantages by reading on.

In the event that the mower starts, let it run for a while so the gas and fuel additives can circulate.

If you still can’t get it started, keep reading to learn about the other fuel-related objects that could be to blame.

SCAG Lawnmower Fuel Filter Clogged

For cleaner fuel, your SCAG mower has a fuel filter installed inline. To prevent debris from clogging the fuel system and damaging the engine, the filter is used to cleanse fuel before it is delivered to the engine.

If the filter isn’t changed regularly, it can become clogged. The mower may turn over but fail to start if a sufficient amount of fuel cannot enter through the filter.

FIX: SCAG gasoline filters are designed to last a long time and may be easily replaced if they become clogged or worn out.

An SCAG Lawnmower’s Clogged Fuel Line

The fuel line must be traced from the fuel tank to the carburetor. If the lawnmower’s engine turns over but doesn’t start, check for fuel flow restrictions.

If there are no creases to be found, then perhaps the gasoline line is too narrow. For starters, you’ll need to use fuel pinch-off pliers or the gasoline shut-off valve to stop the fuel from flowing.

Once the gasoline supply is turned on, remove the ends of the line farthest from the tank and place it in a container to ensure adequate flow through the rest of the line.

FIX: The problem can be solved by disconnecting the fuel line from the mower and turning off the fuel supply if fuel is not flowing through the line.

Distribute carburetor cleaner through the pipe. This is done in an effort to break up the obstruction. The next step is to use compressed air to blow the obstruction out of the line. Carburetor cleaning and compressed air should be used repeatedly until the obstruction is gone.

After the obstruction has been cleared, the gasoline line can be replaced. If the obstruction cannot be removed or if the gasoline line is old and showing signs of cracking, you should replace it.

SCAG Lawnmower Has a Faulty Fuel Pump

When the carburetor of a SCAG mower is mounted above the gasoline tank, the mower requires a fuel pump. When pumping fuel upward to the carburetor, gravity acts as an obstacle that must be overcome by the pump.

A vacuum fuel pump is standard on most mowers. The fuel is sucked into the pump by the crankcase vacuum and then sent on to the carburetor.

If the gasoline pump develops a fracture or stops functioning properly, you will need to get a new one. Even if you can’t detect any obvious damage, such as a crack, you should nonetheless inspect the fuel pump.

Make sure fuel is entering the pump’s inlet port before you try it out. (If not, perhaps there’s a clog in the gasoline line or fuel filter.)

FIX: Once fuel flow to the pump has been verified, disconnect the fuel line from the carburetor and set it aside. Start the gasoline flow and the mower to make sure the pump is working properly.

It’s normal for the fuel supply to the engine to be either consistent or pulsing. A new fuel pump is required if this is not done.

Check the fuel pressure with a fuel pressure gauge if your SCAG has an electronic fuel-injection pump. For information on the ideal fuel pressure for your SCAG, please consult the owner’s manual.

If the fuel pressures are below the engine manufacturer’s recommended level, you should replace the fuel pump.

SCAG Lawnmower with a Filthy Carburetor

Combustion in the engine is achieved by introducing gas and air into the carburetor and mixing them together. Your SCAG won’t turn over if the carburetor isn’t supplying enough gas.

Bad gas is usually at blame when a carburetor stops working. Varnish left behind by old gas can block the fuel jet and cause internal parts to stick.

When the carburetor stops operating, the solution is to either cleanse it, replace the broken pieces, or get a new one.

Do this before you start dismantling your SCAG carburetor:

• Seek reassurance that the carburetor is receiving adequate gasoline.
• Take away the air filter.
• To get the mower going again, spray some carburetor cleaner into the air intake. It’s likely that your carburetor is dirty if it starts up after using carburetor cleaning but then runs poorly and potentially shuts off after the cleaner is gone.
• Disassemble the carburetor, cleanse it, or get a new one

Fuel Drain Blocked on SCAG Gas Cap

Venting the fuel tank allows the pressure inside the tank to become uniform with the outside air pressure. The SCAG lawnmower’s gas cap serves as the machine’s vent.

If the cap’s vent becomes blocked, no air can escape the gasoline tank, creating a vacuum. There is no gas to enter the carburetor because of the vacuum. Due to a lack of petrol, the lawn mower will turn over but will not start.

Loosen the gas cap and try to ignite the mower to see if that solves the problem. The gas cap could be the problem if it fires up.

Just let mower run as you tighten the cap to be sure it’s the cap and not something else. In the event that it sputters, shuts down, and refuses to restart unless the cap is loosened.

The solution is to get a new gas cap if the old one is leaking or clogged.