SOLVED: 13 Reasons Why a Honda String Trimmer Won’t Start!

In order for the engine to start, a sufficient amount of air and fuel must be introduced, and this mixture must be ignited by a spark.

A Honda string trimmer won’t turn over if the air filter is clogged, the spark plug is bad, the fuel filter is clogged, the fuel line is clogged, the carburetor is dirty, the recoil starter is broken, the fuel tank vent is clogged, the spark arrestor is clogged, or the fuel is old.

In addition to a flooded engine, the following issues may be preventing your vehicle from starting.

Remove the spark plug wire and ensure all moving parts have ceased before attempting repairs on your string trimmer. The Honda operator’s manual will have information on how to use the trimmer safely.

Possible causes of Honda string trimmer not starting:

  • Stuck air filter
  • Lack of spark
  • The Fuel Filter is Clogged
  • False gas
  • Incorrect or insufficient motor oil Outdated fuel
    broken primer bulb
  • Fuel line obstruction
  • Diesel tank drain plug
  • Dull carburetor
  • Poor recoil-starting
  • Spark arrestor with a plug
  • Submerged engine

Possible Causes of Your Honda String Trimmer’s Refusal to Start

If you haven’t done so recently, replace the fuel filter, the air filter, and the spark plug when dealing with a starting problem. This will eliminate the possibility that these routine service components are at fault.

These parts should be replaced as part of your Honda’s annual scheduled maintenance.

1. Honda String Trimmer with Attached Air Filter.

Your Honda string trimmer’s air filter keeps the motor clean and safe from debris and dust.

The use of a string trimmer results in a dusty, unsanitary environment. If the air filter isn’t regularly cleaned or replaced, it can become clogged and restrict airflow.

Due to a lack of oxygen, the motor refuses to turn over. If this is the case, you need to make sure you’re always using an air filter with your string trimmer.

This could end up being quite expensive. If dirt gets into the engine’s air intake, it can cause serious problems. The string trimmer might get wrecked to the point where it needs to be replaced.

To fix this, take out the air filter and clean the housing thoroughly. If your air filter is dirty, you should get a new one. Follow the steps below to clean the filter if it is in good condition and only slightly dirty.

How to Replace the Primary FOAM Air Filter in a Honda String Trimmer:

  • Take out the air filter and the cover.
  • Foam air filters can be cleaned with warm water and a mild detergent.
  • Make sure the water coming out of the filter is clear, and then set it aside to dry in the air.
  • After the filter has dried, it should be lubricated with filter oil. Remove any excess oil by squeezing the filter.
  • Put the filter back in.
  • The air filter cover must be reattached.

2. Honda String Trimmer with a Faulty Spark Plug.

Carbon deposits on the spark plug make it less effective over time. The spark plug may misfire, leading to sporadic starting issues.

Incorrect spark plug gap, loose spark plug wire, and cracked porcelain or burned electrode should also be checked. Your Honda may have trouble starting due to any of these factors as well.

A dirty spark plug can be cleaned with a wire brush and possibly reused. I’d rather get a new one. It’s a low-priced essential for keeping your string trimmer operational.

Check that the spark plug wire boot is properly attached and that the gap between the plug and the spark plug is as specified by the manufacturer.

3. Honda String Trimmer with Clogged Fuel Filter.

A tiny filter is connected to the fuel line in the tank. This filter is installed before the fuel pump to prevent dirt and other debris from entering the fuel system.

If you don’t regularly replace your Honda’s fuel filter, the fuel flow to the carburetor could be restricted, making starting difficult.

SOLUTION: Open up the gas tank and replace the fuel filter.

  • Remove the fuel cap and wipe the area around it to get rid of any dirt.
  • The gas tank should be emptied into a new container.
  • Put the cutter down on a level surface.
  • To remove the fuel filter from the tank, hook the fuel line with a clean, bent wire. You could also try using needle-nose pliers.
  • Grab the fuel line firmly and then pull the filter out of the fuel line.
  • Replace the old fuel filter with a new one.
  • Reinstall the fuel filter inside the tank.
  • Refill with clean fuel
  • Replace the fuel tank’s cap.

4. Honda String Trimmer With the Wrong Gas.

Straight gas is required for Honda 4-cycle string trimmers. Fuel with an octane rating of 87 or higher and no more than 10% ethanol should be used.

Avoid using ethanol-rich fuels at all costs. The best fuel to use is one without ethanol.

The answer is to empty the tank and refill it with the proper fuel.

5.Honda String Trimmer With Inadequate or Wrong Oil.

The oil and fuel tanks for a Honda string trimmer with a 4-cycle engine are located in different compartments.

For this engine, you will not combine oil and fuel. Putting the right kind and amount of oil in your engine is crucial.

Never attempt to operate a 4-cycle Honda string trimmer with 2-cycle engine oil. The Honda manual for the string trimmer specifies 10W-30 engine oil. The Kawasaki motor oil is reliable.

The engine’s moving parts can’t function without oil. Not only will your string trimmer not start, but the engine could be damaged if the wrong kind of oil or not enough oil was used.

The answer is to change the oil and put in the proper grade of oil. It may be necessary to adjust the viscosity of the trimmer’s fluid if you plan on using it in extremely cold or extremely hot weather.

If the problem persists, take it to a small engine mechanic so they can assess whether or not it can be fixed affordably.

Honda 4-Cycle String Trimmer Engine Oil

Honda String Trimmer 4-Cycle Engine Oil

6. Burnt-out Honda String Trimmer Fuel.

In addition to causing fuel restrictions, using old fuel in a Honda string trimmer can damage the carburetor and the engine. After only 30 days in storage, gasoline can start to degrade.

Most gasoline contains ethanol, which is a moisture magnet. The fuel system becomes gummed up with moisture and ethanol, and the components corrode.

Fuel should be used within 30 days of purchase due to the rapid deterioration of gasoline after storage. If you won’t be using the fuel within that time frame, you can increase its storage life by adding a fuel stabilizer.

How to choose the right gas for your Honda string trimmer and store it:

  • Never use anything lower than regular (87 octane) unleaded gasoline that contains more than 10% ethanol (E10).
  • Never put E15 or E85 in the engine; doing so will cause damage and will likely void any warranties you have on the vehicle.
  • Make sure to use new gas and finish it off within the month.If you are unable to quickly consume fuel, an additive can be used to lower moisture levels, clean the fuel system, and increase gas stability.
  • A fuel stabilizer should be added to new fuel. It won’t make old gas work again.

The problem can be solved by eliminating any stale gas from the string trimmer. Put some new gas and fuel stabilizer in a clean, approved gas can. To combine the fuel and stabilizer, gently shake the container while it is still covered. Fill up the Honda’s gas tank with the concoction.

Sea Foam Motor Treatment and STA-BIL are two of my favorite fuel additives for keeping gas from going bad. All of my small engine tools have it added to their fuel tanks regularly.

7. Honda String Trimmer Faulty Primer Light Bulb.

If the Honda primer bulb is broken and won’t fill with fuel, it won’t work right to get fuel to the carburetor so the string trimmer can start.

SOLUTION: Make sure that the fuel line is securely attached to the primer bulb. Change a fuel bulb that is broken with a new primer bulb.

8. Honda String Trimmer with Blocked Fuel Line.

Gummy deposits left behind by old fuel can impede fuel flow and damage your string trimmer. This prevents the engine from starting because it can clog the fuel line.

If the fuel line on your Honda string trimmer is broken, bent, or clogged, replace it immediately.

9. Honda String Trimmer with Blocked Fuel Tank Vent.

A Honda string trimmer’s fuel tank vent is typically integrated into the cap. The fuel tank’s air intake vent is there to let fresh air in as fuel is used up.

If the fuel tank stops venting, a vacuum forms that prevents fuel from reaching the carburetor. The trimmer won’t turn on if the carburetor isn’t fueled.

If you are having trouble starting your string trimmer without first removing or loosening the fuel cap to let air into the fuel tank, this could be a sign of a problem with the venting system in the fuel tank.

Allowing the trimmer to run with the fuel cap tightened will confirm the fuel tank vent is the problem if it starts. See if it turns off and won’t start again unless you loosen the fuel cap.

Releasing pressure in the tank by removing the cap and replacing it is the solution.

10. Honda String Trimmer with a Filthy Carburetor.

The carburetor controls how much fuel and air are injected into the cylinder for combustion. It’s not uncommon for the carburetor to become clogged due to old fuel sitting in your trimmer.

To get your Honda going again, you’ll need to clean or replace the carburetor.

Clean your carburetor yourself if you’re at all mechanically inclined. Take apart the carburetor and clean it with carburetor cleaner.

After cleaning, if the carburetor still doesn’t work, you may need to have it rebuilt or get a new one.

Depending on the age of your string trimmer and the cost of a carburetor, you might be better off purchasing a brand new Honda model rather than repairing your current one.

Compare your current Honda’s price, age, and model to that of a brand new Honda string trimmer.

11. Honda String Trimmer with Faulty Recoil Starter.

The engine of your Honda string trimmer is started with a recoil. Recoil systems can stop functioning due to faulty pulleys, missing or loosened springs, or damaged clips.

Recoil spring replacement and restringing is one possible solution.

If the pulley or clips in your recoil are broken, the whole assembly should be replaced rather than trying to fix it.

12. The Honda String Trimmer’s Spark Arrestor Was Clogged.

A Honda string trimmer has a spark arrestor and a catalytic converter. The spark arrestor is a small screen installed in the exhaust pipe of your Honda to contain flying sparks and embers that could cause injury or a fire.

Clogged with soot, the screen prevents the hot exhaust air from escaping the trimmer. A Honda trimmer may refuse to turn on if this happens.

REMEDY: Take off the cover on the spark plug. Be wary of a hot engine. The engine cover and the exhaust cover must be removed.

Take out the spark arrestor and scrub the soot off with a wire brush. If the spark arrestor screen has a hole, is damaged, or cannot be cleaned properly, it must be replaced.

13. Honda String Trimmer Submerged in Water.

It’s possible that you flooded the engine trying to start it. This is not a major issue that requires urgent attention.

When the choke is closed and the starter rope is pulled repeatedly, too much gas can enter the carburetor and flood the Honda engine.

It can also occur if the primer bulb is pushed too many times or the starter rope is pulled repeatedly while the switch is off.

SOLUTION: If your string trimmer won’t start because the engine isn’t getting enough air, “unflood” it by following these steps.

Fixing a Honda String Trimmer’s Overheated Engine

  • Flip the switch from the off to the on position.
  • Adjust the choke to “run” or “open.”
  • Repeatedly pull the starter rope and press the throttle trigger to start the engine. There may be a delay of up to fifteen pulls before this begins. First, the motor on your string trimmer will start to sputter. If you keep pulling it should turn on.