Gas powered lawn mowers are incredibly efficient and reliable tools for maintaining your garden. But their complex combustion engines mean that they require a lot of maintenance and it’s always possible that things might go wrong.
One of the problems you might experience is a flooded lawn mower which can stop the machine from starting. But do you know how to unflood a lawn mower?
Normally, you will be advised to allow the engine to settle for around 15 minutes which will give the carburetor a chance to dry. But if you’re in a hurry, there is a much quicker method.
If you’re standing in your garden wondering how you’re going to get your flooded lawn mower going again, you’re in the right place. Here you’ll find everything you need to know to fix this common problem.
Before you start panicking that your lawn mower is flooded, you should take the time to consider whether it actually is. It could be that there are other issues at play and your mower isn’t flooded at all.
There are so many things that can cause a petrol lawn mower not to start so begin troubleshooting to find out where the issue lies and if it is that your lawn mower (is) flooded. Here are some of the signs you can look out for.
You Smell Gas When Starting Your Mower
If you have attempted to start your lawn mower and nothing is happening then pay attention to whether you can smell anything. If there is an obvious aroma of gas in the air then it’s pretty certain that you have a flooded lawn mower engine.
Remove The Spark Plug And Smell It
If you don’t want to rely on the smell when trying to start your lawn mower then you might have a sniff of the spark plug as this can tell you a lot. Just take the spark plug out and smell it. If you can smell gasoline then it’s an almost certain sign that you have a flooded lawn mower and you will need to keep reading to learn how to fix the problem.
Guide On How To Unflood A Lawn Mower
If you have found yourself with a flooded lawn mower that won’t fire up then there is nothing quite as annoying. A lot of people think that this will be the end of the road for their machine but that isn’t usually the case. You can follow the steps we are about to detail and, nine times out of ten, you’ll be back up and running before you know it.
Remove The Spark Plug
You might already have the spark plug out if you used this method to test whether the lawn mower flooded but if not then you will need to remove it now. Take off the spark plug connection and then use a spark plug wrench to take the spark plug out.
You will probably notice that the terminals are covered in fuel so you will need to dry them off before you do anything else. You can use alcohol based starter fluid for this or, if you prefer, use a dry cloth to wipe the terminals over.
Crank The Engine
Keep the spark plug removed and now crank the engine a couple of times. When you do this, stand well clear from the front of the engine. As you crank it, air will move through the carb which should help everything dry out more quickly.
Replace The Spark Plug
It’s now time to replace the spark plug. When you have done this, try turning the choke off and cranking the engine again. It might sputter at this point but give it a couple more goes and it should start up. If not, then you might need to turn the choke back on but once the engine gets going, be sure to turn it right back off.
Spray Air Filter With Starter Fluid
If the mower engine does not sputter you should now remove the air filter. In a lot of cases, you will need a screwdriver for this so make sure you have one handy.
Once it is out, spray the air filter with starter fluid before quickly replacing it and cranking the engine once again. If nothing happens then you will need to take the air filter back out and continue cranking the engine without it as this should aid in emptying the carb.
If you find that the engine sputters after you have removed the air filter then this is a sign that it is dirty and needs to be replaced.
How Long Does It Take To Unflood A Lawn Mower Engine?
While the above method requires a little more effort from the user, it is generally much quicker. However, even without using this method, you should be able to have your lawn mower engine unflooded within around twenty minutes. It’s really not a long process.
To do this, you will need to make sure that the mower is on a level surface and just wait. That’s really all there is to it. During the 15 – 20 minutes it takes, the excess fuel will evaporate and it’s highly likely that the lawn mower will fire up and you can get on with the job.
For the most part, this is a problem that’ll sort itself out. Of course, there will be times that you have to admit defeat and take the mower to a repair shop but for flooded engines, this is rarely the case.
How Does A Lawn Mower Engine Get Flooded?
Gas lawn mowers run on pretty complex engines that are made up from several different parts. Each of these parts is essential in the running of the engine and if one doesn’t work, everything will fail.
You have a carburetor which is responsible for mixing fuel and air while the pistons draw in this mixture to compress it. There is also a spark plug which, as its name suggests, creates the spark required to ignite the engine.
You’ll notice there is a lot of talk about air and fuel mixture when it comes to combustion engines and if the ratio between these two substances isn’t spot on, combustion cannot happen. If there is too much gas, this is what can flood the engine and prevent the mower from starting.
Final Thoughts
If you’re trying to get your lawn mower going and nothing is happening, it could be that you have a flooded engine. But not many people know how to unflood a lawn mower and certainly don’t realize how easy it is.
You could sit and wait for the fuel to evaporate which usually takes around 20 minutes. But you can also remove the spark plug and crank the engine as well as using starter fluid on the air filter which will usually solve the problem.