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Honda Lawn Mower Won’t Idle

Honda engines are some of the toughest in the industry. Their lawn mowers are known for lasting a long time, but idling tends to cause problems occasionally. Whether you’re trying to fix or prevent this issue, Honda makes it easy to find a solution. No more waiting around trying to idle a mower!

A Honda lawn mower might not idle due to a dirty carburetor. Accumulated debris and old fuel can clog the carburetor, affecting its operation. Cleaning the carburetor thoroughly can solve this issue, ensuring the mower idles smoothly. It’s a straightforward fix that can restore your mower’s performance.

Another reason your mower may struggle is due to a faulty spark plug. A spark plug is essential for igniting the fuel in your engine, and if it’s worn out or dirty, it won’t work properly. Replacing the spark plug is an easy and cost-effective solution that can often bring your mower back to life. It’s like changing the batteries in a remote; suddenly, everything works as it should.

Lastly, the problem might stem from a fuel issue, akin to trying to start a fire with damp wood; it just won’t catch. If your mower has been sitting idle for a long time, the fuel could have degraded or become contaminated, leading to poor engine performance.

Draining the old fuel and refilling the tank with fresh gasoline can often resolve idling issues, much like using dry wood ensures a good fire. This simple change can make a significant difference in how your mower operates.

Throughout this article, you’ll also learn the following information about why your Honda lawn mower won’t idle:

  • Various reasons that cause a mower not to idle
  • Fixes for every cause of this common problem
  • How you can prevent your lawnmower from having idling troubles

Why Won’t My Honda Lawn Mower Idle?

Honda mowers are at the top of the yard care business. They’re reliable and easy to repair, which is why you shouldn’t worry too much if yours won’t idle.

Before you start repairing the mower, it’s important that you know the different causes. You’ll also be able to prevent it from happening again.

Here’s a list of the five most common reasons that Honda mowers won’t idle:

  • A bad throttle cable can be the root cause of your Honda’s troubles. It’s not too rare for an old throttle cable to need repairs or replacements. The main purpose of this part is to adjust the speed of the blade and engine. When it’s worn, it won’t be able to maintain an even pace, otherwise known as idling the engine.
  • Repair Clinic suggests that a malfunctioning carburetor could be the problem. A clogged carburetor could prevent the engine from working as it should. You’ll notice that it continues to stall every time you try to start the mower. You might have to replace the carburetor or clean it, depending on the severity of the clog.
  • Spark plugs are sometimes the cause, but they’re never too big of an issue. In fact, if the spark plugs are the primary reason that the mower won’t idle, then you’re in luck. Replacing spark plugs is often one of the cheapest lawnmower repairs that you can do. They usually don’t cost more than one to two cups of coffee.
  • Coagulated, old gasoline or oil is a major concern for lawn mower owners. If you’ve never read about maintenance tips, then you should know that you can’t leave fuel in a mower for too long. It starts to become thicker, almost as if it were made of slime. This consistency can ruin the engine, including the carburetor, as mentioned above.
  • The fuel cap might be the culprit. Much like spark plugs, fuel caps aren’t too expensive. There’s typically an O-ring in a fuel cap that seals outside air and moisture from getting into the fuel tank. When the ring wears down, or the cap is loose, moisture can get inside and tamper with the gasoline and oil.

As you can see, there are plenty of reasons why your Honda lawn mower won’t idle. Luckily, most of them are inexpensive or easily avoidable.

However, if you happen to run into these troubles, don’t stress too much. The next section will cover fixes for all five issues to keep your mower running strong.

How to Fix the Common Problem

Fixing your Honda mower doesn’t have to be a costly headache. Fortunately, there are dozens of online video guides to take you through the process, including this one by Mower Man:

Below, you’ll find every fix for each cause of your Honda’s non-idling engine:

  • Bad throttle cables often have to be replaced. Unfortunately, there aren’t too many repairs that can be done. The good news is that all you have to do is turn off the mower, unscrew the throttle cable housing, wind it off, and lace the new cable. Test the tension and repeat the process until it’s as tight as the previous cable.
  • Carburetors either have to be replaced or thoroughly clean. If it’s not too far gone, you can clean it easily with WD-40 Specialist Carb/Throttle Cleaner. Spray it on, let it sit for about 30 seconds, then wipe it off. You’ll have to remove all of the old oil and other debris sitting on the surface for it to work properly.
  • Spark plugs are the simplest repair in the industry. You’ve probably used spark plugs in other engines, such as vehicles or yard care products. Turn off the system, remove the old spark plug, and twist in the new one. It’s that easy! Be sure that the mower is unplugged if it’s electric and completely off, even if it’s gas-powered.
  • Old gasoline and oil cause problems because they can get grimy. When they’re left to sit in the tank for too long, they start to coagulate. Once the liquids get too thick, they can’t be burned properly. You’ll have to remove the old oil by siphoning it out. Do your best to clean out the tank, then add new oil and gasoline.
  • A fuel cap allows rainwater, moisture, and other debris inside of the fuel tank. Needless to say, moisture dilutes the fuel, causing it not to burn properly. Replace the fuel cap’s O-ring if it’s the cause. Otherwise, you might have to replace the fuel cap according to the make and model from Honda.

Preventative Measures to Consider

Preventing your mower from idling is easier than repairing or replacing parts. Furthermore, it costs a whole lot less money. As long as you follow the tips found below, you’ll be all set for many years to come.

Lubricate All of the O-Rings

As mentioned earlier in the article, O-rings are designed to keep out moisture. You can use silicone lubricant, such as Super Lube, to prevent the O-rings from getting dry and cracked. A budget-friendly bottle will last you several years, and you can use it on any O-ring on any motorized system.

Copyright article owner is for this article. This post was first published on September 11, 2020.

Move Your Mower and Remove Fluids When It’s Unused

One of the best ways to preserve your Honda lawn mower is to remove the oil and gasoline when it’s the off-season. If you know you’re not going to be using the mower, then remove the fluids to prevent them from coagulating. Once you’re ready to start mowing again, you’ll have a fresh, clean tank to work with.

Clean Your Carburetor Often

The carburetor tends to get dirty on all mowers. There’s not much you can do to prevent it from getting messy, but cleaning it more often will stop a problem in its tracks. Clean it with the aforementioned carb cleaner monthly (or more, depending on how often you use the mower) to prevent gunk from building up.

Final Thoughts

Your Honda lawnmower likely won’t idle because it has a fuel-related problem, but there are many other causes. Fortunately, we’ve covered everything you need to know to keep your mower in good shape throughout the upcoming years.

Here’s a quick recap of the post:

  • Spark plugs, O-rings, and throttle cables naturally wear down over time.
  • Never let old gasoline or oil sit in a lawnmower for too long.
  • Clean your mower’s carburetor regularly to prevent idling issues.
  • Make sure you keep the O-rings lubricated to keep out the moisture.
  • Spark plugs and fuel caps are cheap, easy repairs.

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