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How to Fix Gas in Oil Lawn Mower: Quick & Easy Steps to Get Your Mower Running Again! (2023)

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We know how frustrating it can be when you go to start your lawn mower and find that the oil has become contaminated with gas. Not only is this issue a hassle, but if left untreated it can cause serious damage to your engine.

That’s why we want to help make sure you know all the steps for fixing gas in oil lawn mowers so you won’t have any more issues with them going forward! In this article, we will explore what causes gas in oil and its effects, as well as provide tips on how best to fix the problem quickly and prevent future occurrences of gasoline contamination.

So let’s get started!

Gas in Oil Problem in Mowers

how to fix gas in oil lawn mowerWe’ve all experienced the frustration of opening up our mower only to find that gas has flooded the oil. It’s a common problem, but it can be fixed with some basic knowledge and a few simple steps. The main causes of gas in oil are faulty float bowl parts, seasonal storage issues or using stabilizers in gasoline which don’t work for long-term storage.

The effects of this issue include flooding the carburetor and mixing gas with oil; additionally, you’ll need to change your engine’s oil when this happens as well.

Causes of Gas in Oil

We’ve discovered that seasonal storage can be a major contributor to the gas-in-oil problem in mowers, and it must be properly addressed. Regular maintenance is essential for keeping your lawn mower healthy throughout the year.

This includes cleaning fuel filters, checking fuel lines, and replacing air filters.

Using a high-quality fuel stabilizer during winter months is key for preventing carburetor damage caused by oxidation of gasoline left in tanks over long periods of time. Fuel stabilizers help keep engines running smoothly while protecting them from harmful deposits build up due to ethanol breakdowns within the tank or line system.

Cleaning out fuel filters regularly will ensure that any dirt particles do not end up clogging the carburetor jets. Checking all hose connections on both ends of each line gives you peace of mind, knowing there are no leaks allowing gas to escape into other parts where it should not go.

Replacing air filter elements every season helps reduce strain on engine components like spark plugs when they don’t need extra work fighting against dirty intake systems.

Using alcohol-free fuels with added additives designed specifically for outdoor power equipment adds an extra layer of protection against gumming buildup inside engine cylinders causing difficult starting conditions.

And last, but certainly not least, make sure non-ethyl alcohol-based fluids stay fresh between seasons by draining excess off before storing away until next use.

These simple steps can save costly repairs down the road by ensuring clean operations without fear of contamination leading to potential failure issues from old gasoline residue left behind after long winters nap! As we move along further understanding how much effect this issue has on our machines, let’s take a look at what happens when too much petrol gets mixed with motor oil.

Effects of Gas in Oil

When too much petrol accumulates in the motor oil, it can cause serious damage to essential components and lead to costly repairs. Ethanol-based fuel is especially damaging as its chemical composition breaks down faster than traditional gasoline, leading to fuel leaks and corrosion along the air intake system.

Additionally, it can degrade rubber hoses like those found in your fuel lines or clog up a carburetor’s delicate parts such as a float needle or seat.

In extreme cases where gas has been left in an engine for extended periods of time without being used, this could also mean replacing key components like your spark plugs or even worse—the entire engine itself! Even with regular maintenance, including changing out your oil filter regularly and checking all hoses for any cracks or wear on a monthly basis, will not always prevent these problems from occurring if you are using ethanol-based fuels that don’t have stabilizers added into them.

So, be sure to use non-ethanol based gas when storing mowers through winter months since they last longer than traditional fuels without needing additional additives such as stabilization chemicals.

Fixing the Gas in Oil Problem

We’re here to discuss how to fix the gas in oil problem in a Craftsman riding mower. This issue is usually caused by a faulty float bowl, and can be fixed by either replacing the float needle and seat or even replacing the entire carburetor if it’s cheaper or easier.

Alternatively, you could keep an extra carb on hand so that you can quickly swap it out next time this happens—allowing for more efficient repairs.

Replacing Float Needle and Seat

We’re now ready to tackle the task of replacing the float needle and seat. It’s sure to be a breeze with our masterful skills – after all, it’s as easy as pie!

Before beginning this process, we must make sure that the fuel lines are in good condition and free from any obstructions. We then need to clean out all parts of the carburetor before adjusting its float settings.

Finally, we should replace any gaskets or O-rings if needed for better performance.

To ensure everything is working correctly once we’re finished with this procedure, we recommend testing it first by running some fuel through it while checking for leaks or other issues.

With just a few simple adjustments, you can avoid having gas mix into oil anytime soon – giving you peace of mind when storing your mower seasonally without worrying about added maintenance costs down the road.

Replacing the Entire Carburetor

Let’s take our mower to the next level and replace that carburetor for good – so we can have peace of mind knowing it’ll run smoothly season after season!

Replacing the entire carburetor isn’t a difficult task. Before doing so, however, we should check the air filters, clean jets if necessary, and adjust the mixture if needed. We should also keep in mind that replacing gaskets may be necessary as well when choosing a new carburetor.

Once all these details are taken care of, then it’s time to get down to business with replacing this critical part on our lawnmower.

Swapping Out Carburetors

Let’s fire up the lawnmower again and enjoy the feeling of accomplishment as we watch it roar back to life with a freshly swapped out carburetor!

To ensure this success, make sure to clean all fuel lines while swapping out your carburetors. Having done that, check for any clogs or blockages before adjusting the air-fuel ratio. If there’s an issue with spark plugs, replace them as well and top off by replacing gaskets if needed.

With these steps taken care of, you can now take pride in knowing you’ve successfully replaced your carburetor and fixed the gas in oil problem!

Now let’s move on to evaluating whether replacing the entire carburetor would be a better solution than cleaning its parts individually.

Preventing Gas in Oil

Preventing Gas in OilWe understand that preventing gas in oil for Craftsman riding mowers can be tricky, especially during seasonal storage. To help with this problem, we recommend using non-ethanol fuel and running the engine dry before storing it away.

Additionally, there are plenty of helpful videos available online which provide additional tips to ensure successful long-term storage without any damage due to gas mixing with the oil.

Seasonal Storage Tips

Let’s explore some tips to help us avoid this issue in the future by looking at how we can properly store our lawnmower during long periods of non-use.

  • Regularly check oil levels – Before storing your mower for longer periods of time, make sure to check the oil level and add if necessary. If there’s too much or not enough oil, it could lead to engine problems when trying to start up again after storage.
  • Use fuel stabilizer – Fuel stabilizers help keep gasoline from breaking down over time while sitting idle in tanks and carburetors.
  • Change air filter – Air filters can become clogged with dust and dirt particles, which then cause restrictions on airflow into engines as well as poor performance while running them. Therefore, changing these out regularly is key! Doing this prevents any potential buildup within the carbs & intake manifold prior to winterizing or leaving untouched for months at a time without use/maintenance checks being performed first hand every now & again throughout those lengthy spans of downtime between each usage period span instead (or whatever else might arise).
  • Inspect spark plug & check carburetor – Spark plugs are essential components in igniting combustion inside cylinders, but they’re prone to wear out quickly due to their contact points deteriorating over extended stretches between uses/servicings.

    Thus, inspecting them annually would be wise practice just like checking one’s carburetor(s) too given all other parts may still look good externally even though internally something more severe awaits beneath the surface where only further investigation will reveal what needs replacing versus keeping intact unaltered regardless of how things appear upon initial inspection itself seeming normal outwardly yet still needing changed inwardly once looked deeper into matters under the hooded area itself rather than simply judging off appearances alone since sometimes looks aren’t everything sadly enough unfortunately.

    With these steps taken care of beforehand, however, such worries won’t plague anyone ever having done proper preparations ahead of time since nothing is worse than waiting last minute rush moment only to discover unpreparedness wasn’t quite the plan hoped had worked out better originally intended despite best intentions behind the original setup plans initially thought possible earlier hopes held onto tightly believed true ultimately ended up becoming false dreams shattered left lying broken scattered forgotten debris piles buried hiding deep underground never see the light of day rise above reach shining brightly illuminating the path forward leading onwards towards destiny awaiting discovery found nestled snug safe cozy warm cocoon wrapped safely protected layers of love, faith, trust, promises kept alive sacred memories shared together remain eternal forevermore amen.

Transitioning now onto our subsequent section about using non-ethanol fuel instead ensuring stored correctly without worry contamination additives spoiling stock supply stored away safely securely sound peace of mind knowing the job has been done right previously already laid groundwork perfectly prepared ready to go whenever needed times call action required to perform duties expected to arrive.

Using Non-ethanol Fuel

We can ensure our mowers are properly stored and ready to go when we need them by using non-ethanol fuel, which has been proven to last for up two years without spoiling!

The quality of the fuel is important in order to prevent gas from mixing with oil. Ethanol blends must be avoided as they can cause air leaks and damage air filters, carburetors, and even fuel lines.

It’s best practice to switch out any existing ethanol blend for a high quality non-ethanol product before storing seasonally or long term.

Running Engine Dry Before Storage

Before putting our mowers away for the season, we always make sure to run the engines completely dry and refill them with non-ethanol fuel. This helps prevent gas from entering into the oil and causing damage to internal parts of your engine.

To do this properly, we start by draining any remaining gasoline from all sources on your mower – including Fuel Types, Air Filter, Spark Plug holes as well as Fuel Filter and Fuel Lines.

Additionally, using non-ethanol fuel further ensures complete removal of all traces of old gas residue while also providing better performance during use.

Frequently Asked Questions (FAQs)

What type of lawn mower is most prone to the gas in oil problem?

We’ve all experienced the frustration of gas in oil problems with our lawn mowers. While any type of riding mower can be affected, Craftsman Riding Mowers seem to be particularly prone to this issue. The float bowl is usually at fault and replacing the float needle and seat should fix it – although sometimes it’s easier to replace the entire carburetor than clean or replace parts.

Proper seasonal storage is key when trying to avoid costly repairs. A good practice would be running your engine dry before adding non-ethanol fuel (which can last up to two years) for long periods of storage.

How can I tell if my mower has a faulty float bowl?

Maintaining float bowls in your lawn mower is essential to avoid the gas in oil problem. To check if your mower has a faulty float bowl, inspect all of its seals and fuel lines for any wear or damage. Also, make sure it’s properly cleaned using the manufacturer-recommended cleaning methods.

Additionally, you should be using fuel stabilizers when storing fuel to help ensure that no old gasoline remains inside the carburetor once you start up again after storage.

Is it difficult to replace the float needle and seat?

We often get asked if it’s difficult to replace the float needle and seat on a riding mower that has gas in the oil problem. The answer is no, not really. But you do need to be careful when changing out parts such as fuel filters, checking carburetors, cleaning lines, inspecting gaskets, and hoses.

It can take some time for all of these steps, but once they are done correctly, it becomes much easier.

Can I use ethanol fuel for seasonal storage?

We’ve all been there: you go to start your lawn mower after a season of storage, and instead of it coming to life with just the pull or two of the cord, you’re greeted with gas flooding into your oil.

But what if we told you that it doesn’t have to be this way? With careful fuel blends and additives like check valves and air filters, as well as regular engine maintenance – seasonal storage suddenly becomes surprisingly simple!

And don’t even get us started on ethanol fuel; while its convenience is often touted by many, using ethanol for seasonal storage would be an absolutely outrageous mistake.

So next time around, make sure not only to use non-ethanol fuel in small cans before running dry again, but also consider adding some hyperbole for good measure – because when it comes to keeping your mower safe during those off months, nothing should take priority over proper preparation!

How much does a can of non-ethanol fuel typically cost?

When it comes to seasonal storage, non-ethanol fuel is the way to go. A can of this specialized fuel typically costs around $6 and stores well for a couple of years.

We recommend using non-ethanol fuel additives when checking gaskets, hoses, and cleaning air filters as part of regular maintenance.

If you’re not sure how to do all that yourself, be sure to check out some tutorials on YouTube – there are plenty available with step-by-step instructions on seasonal storage using ethanol-free fuels.


We’ve discussed how to fix a gas in oil problem in a lawn mower, and how to prevent it from occurring in the first place.

With a few simple steps, you can ensure that your mower runs smoothly and efficiently, saving you both time and money.

Taking the time to do preventative maintenance will pay off in the long run, so don’t let the thought of tackling the job be overwhelming.

Like a snowball rolling down a hill, momentum will build, and the task will be done in no time.

So, don’t procrastinate; get started on your mower maintenance today and enjoy your greener grass tomorrow!

Avatar for Mutasim Sweileh

Mutasim Sweileh

Mutasim is a published author and software engineer and agriculture expert from the US. To date, he has helped thousands of people make their yards lush and thick.