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Lawn Mower running rough?

Is your lawn mower running rough but you have no idea how to fix it? Well don’t worry, this quick guide will give you all the information you need to get your mower running as smooth as the day you brought it home. Make no mistake, this guide is for everyone. You don’t need to be particularly handy, lawn mowers are simpler than you think and there’s really nothing you can do that will cause any major harm. See also Lawn Mower Repair Tips
Lawn Mower running rough

When a lawn mower is running rough it normally comes down to one of 4 things. Faulty spark plugs or plugs that are installed incorrectly (might have wiggled loose), a blocked air filter that needs to be cleaned or replaced, the fuel filter is clogged or the petrol you are using is incorrectly mixed. Let’s take a look at each of these in more detail. I promise if you follow these 4 simple steps, your mower will be back up and running in no time.

  1. Air Filter: Check the air filter on your lawn mower is clean. If it is clogged, simply clean and replace. If it has tears or is beyond repair this should be replaced. A constant stream of filtered air is vital for a lawn mower. A clogged filter starves the engine of the oxygen it needs for combustion.
  2. Petrol: When filling up your mower you would probably be aware that using petrol with 10% ethanol is believed to cause problems in small engines like lawn mowers (this is the normal petrol you put in your car) Further, blended fuel, again like what you put in your car, doesn’t have the longest shelf life. If you are like me, you are probably not using your mower as often as you should. Ethanol mixed fuel can actually go bad if it is left sitting in your lawnmower between uses. This clogs up your mower and it won’t run the next time you use it. I always recommend you use ethanol-free petrol, this can be purchased at most hardware stores (Google ethanol free fuel and your suburb and a bunch of retailers will pop up). It is also a good idea to also add fuel stabilizer as this will increase the time you can store the petrol before it needs to be replaced.
  3. Spark plug requires replacement or re-fitting: Remove the spark plug from the mower and ensure it is not clogged or clearly damaged (cracked insulator or the electrode has burned away). If needed, replace the plug. When replacing the plug ensure you use a spark plug gap gauge. When doing this ensure the gap is set to the distance specified in the manual for your lawn mower. If a spark plug is installed with the wrong gap setting, it can quickly become fouled with carbon.
  4. Fuel Filter: Finally, check the fuel filter on your mower to ensure it is clean. If the fuel filter gets blocked your motor simply can’t get enough fuel to run smoothly, or potentially run at all.

If you have worked through all of these steps your mower should now hopefully be back up and running. If you are still experiencing issues it could be a more serious problem and it’s probably best to drop into your local mower repair shop. With any luck, however, this article saved you the trip!