Common Engine Issues and Solutions for Lawn Mowers

Submitted by Anonymous (not verified) on Mon, 05/10/2021 - 9:52am

Take Care of Your Lawn Mower Engine

Take Care of your John Deere Lawn Mower Engine

Owning a lawn mower is like owning a vehicle, sometimes you will experience common issues that are just a part of ownership. Below we will cover a few common engine issues such as what to do if you put the wrong fuel in the fuel tank, what happens if there’s water in the fuel and more. Along with these issues we will also review some solutions to ensure any engine issues are caught in a timely manner and can be fixed properly.

What happens when I mix regular gas with diesel fuel or kerosene in my lawn mower?

Sometimes mistakes happen! If you mess up and put diesel into your gas lawn mower, you can still save your lawn mower. Lawn mowers are low compression so a little bit of diesel shouldn’t hurt anything too much. However, there is a risk that it will cause the mower to smoke rather badly. The best thing to do is to drain your tank immediately, refill it with gas and replace the fuel filter. Once you do so, you should be good to go and can continue mowing. It may smoke for a few minutes as it clears out the remaining bad fuel but should clear up quickly.

It is not recommended to add kerosene to your gas lawn mower, but we also understand mistakes happen. If a little bit of kerosene is mixed with your regular gas, there will not be any noticeable short-term effects. If there is around 15-20% kerosene in your gas tank, your mower is going to run rough at some point, then quit running all together. Repairs will potentially be needed beyond removing the bad fuel and putting in a clean fuel filter.

The best practice is to have multiple fuel cans, each for a specific fuel type.  Color coded cans are available (red for gasoline, yellow for diesel, and blue for kerosene), or you can label them with a permanent marker.  It’s also a good idea to have a separate can for mixed fuel used in trimmers or chainsaws.

What happens if there’s water in my gas lawn mower engine?

Springtime is a very common season to find water in your mower from condensation in the gas tank. If this water is not addressed, it can get into your lawn mower’s engine and cause some major performance problems. Not only do you risk performance problems, but you also risk some major long-term damages as well. Some of these long-term damages include corrosion in the tank, carburetor and fuel lines. When excessive corrosion happens to these parts of the lawn mower, it becomes very costly to repair.

If water does happen to occur in the engine oil, you can drain it and avoid long-term damage. To drain the water, you will need to start with the crankcase on 4-stroke engines. If water comes out with the oil (it will look milky in color), you will need to add some light oil, turn the engine over a couple times using the starter, and drain it again. Remove the spark plugs first, to discharge any oil from the cylinders and to make sure it does not start during the process.

What does it mean if my lawn mower is smoking?

Sometimes you will notice your lawn mower is putting off black exhaust smoke. The gasoline to air mixture is regulated in the lawn mower’s carburetor. If there is not enough air getting into the carburetor, then there is a higher ratio of gasoline which results in black exhaust smoke.

If your lawn mower does start smoking like this, you do not need to panic. The most common cause of a smoking lawn mower is a clogged or dirty air filter. When the air filter is not clean, the carburetor is unable to pull the proper amount of air in to keep the correct ratio of gasoline to air. Once the mower is shut off, check and replace the air filter and give it another try.

Routine maintenance (at least once a year) is key to avoiding many issues.  A fresh oil change and new filters are inexpensive, and far less than major repairs.  Consult your operator’s manual for a list, or contact us for assistance.

Where can I find lawn equipment maintenance and repair services?

Finding lawn equipment maintenance and repair services for equipment does not have to be time consuming or overwhelming. The expert technicians at Koenig Equipment are trained to fully inspect your mower and repair any and all issues so schedule the service you need today.


Written by Boland Media


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