Can Lawn Mower Get Wet?

Do you have an electric or gas lawnmower and you accidentally left it out in the rain? Maybe you just washed it or you want to use it but all the grass is wet. Can your lawn mower get wet? What will happen?

I was wondering too so I decided to find out.

Yes, your lawnmower can get wet and still function. You can even use it to mow wet grass though there are reasons that you may want to skip that. Generally you should wait for it to stop raining and for the grass to dry out a bit so it’s easier on your engine.

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Is A Lawnmower Waterproof?

No, lawnmowers are not waterproof. You can’t use them to mow the bottom weeds of your yard pond. Also, it’ll be tough on the engine if you cut the grass in the rain.

Sources of Water that can cause a problem

Rain

This is the first and most obvious way your lawnmower can get wet. Either it’s left out in the rain or you want to mow while it’s raining out.

Puddles

Puddles that form in your yard after a rain are another issue. If you mow through them you might splash water up on the engine block. A hot engine block doesn’t do well when it gets hit with cool water.

You always want to wash your mower after the engine is cool. It’s the same thing with rain or puddles. From what I can find, experts agree it’s better not to let cool water hit a hot engine if you want to prevent it from getting damaged.

Wet Grass

Wet grass is the second most common way your lawnmower will get wet. You waited for the rain to pass. You don’t have much weekend time available and you need to cut that grass.

Running your lawnmower through wet grass has it’s issues which we’ll cover below.

Flooding

Perhaps you live in a floodplain or somewhere prone to hurricanes. It’s likely at some point your lawnmower will get completely submerged in flood waters.

If and when this happens you want to give it plenty of time to air out prior to starting it. It’s also a good idea to check the gas tank for water and possibly remove the gas, safely dispose of it, and add new gas.

Washing Your Mower

This is the last and least worrisome way to get your lawnmower wet. It’s perfectly safe to wash your lawnmower as long as the engine is cool.

Is It Bad To Mow Wet Grass? 9 Reasons Not To Mow In the Wet

Here’s some of the top reasons not to mow wet grass. You can do it but I found that it was better not to.

  1. Wet grass sticks to the ground and can’t be mowed evenly. Some parts will be get pulled into the mower. Others will stay low leaving your yard looking choppy.
  2. Moisture in the gas tank can cause corrosion and engine problems.
  3. Wet metal parts can rust.
  4. Wet grass is harder to mow and tougher on the engine.
  5. Mowing wet grass with an electric lawn mower is dangerous to you, the mower.
  6. Mowing wet grass on slopes is also dangerous. You could slide off with a moving mower blade that could seriously injure you.
  7. Even on flat areas you could still slip while mowing and injure yourself. Imagine slipping and having your leg slide under the mower. No bueno.
  8. Wet grass will stain your shoes and clothes.
  9. It’s harder to push a mower over wet grass.
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Is it OK to mow in the rain?

No, it’s not ok to mow in the rain for all the reasons mentioned above on mowing wet grass. It’s harder to push a mower in wet grass. It’s significantly more dangerous (slips, electric lawn mower shocks). Plus the rain itself could get in your gas tank, cause corrosion on metal parts, and could hurt the hot engine.

Lastly, it’ll just do a bad job. Some spots will be wet and sink low getting missed by the lawnmower. You’ll end up with a checkerboard yard of high and low spots.

Nobody wants that.

Can I Run A Lawnmower Through Puddles?

No, you should not run a lawnmower through puddles. What if you slip and hurt yourself? What if the puddle is deeper than it looks? What if that water gets in the gas tank?

There’s a lot of things that can go wrong if you run your lawnmower through a puddle. It’s also a sign that the grass is still wet.

It’s much better if you wait for the water to sink into the ground and for the grass to dry out a bit more.

Will Rain Or Water Damage My Gas Lawnmower?

A little rain or water won’t hurt your lawnmower. It’s designed to get wet from time to time. It’s washable.

You may end up hurting the lawnmower if you use it for extended periods in the rain or on wet grass. If water gets into the gas tank, the air filter, or the carburetor you may have trouble starting it again in the future.

Can Electric Lawnmowers Get Wet?

After reviewing a few instruction manuals it became abundantly clear to me that electric lawnmowers should never get wet or be used in the rain.

Some electric lawnmowers use lithium ion batteries that can never get wet. They are actually a fire and explosion risk. Remember those phones a few years ago that weren’t allowed on planes because their batteries kept catching on fire?

Most electric lawnmowers are plugged in giving you maximum power. To do the whole yard you’ll end up using extension cords. Every place that extension cord is plugged into your lawnmower cord is a danger zone that could electrocute you.

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Is It Bad To Start A Lawnmower After It Got Wet In The Rain?

Possibly. If moisture got in the air filter or carburetor your lawn mower may have trouble starting. Simply let it air dry for a bit prior to trying again.

Once it starts go ahead and let it run for a bit. The heat of the engine will naturally dry out the air filter, carburetor, and other components.

Lawnmower Parts That Can Get Affected By Water

Here are the most common parts that can get hurt by water:

  • The carburetor gets moist and the engine won’t start
  • Water gets in the gas tank and causes corrosion or performance problems. Water will sink to the bottom of the tank causing corrosion and a leaking tank.
  • The air filter is wet
  • Lawnmower blades get wet, rusty, and dull
  • Other metal parts get wet and corroded

What To Do If Your Lawnmower Gets Wet

Here’s a few steps to take when water gets into your lawnmower:

  • Wet lawnmower – let your lawnmower fully air dry. Turn it on and let it run for 15-30 minutes. The heat of the engine should dry out the carburetor, air filter, spark plugs, and most components.
  • Water in gas tank – drain the gas tank and properly dispose of the gas/water mix. Add new gas/oil.
  • Water in oil – When water gets in the oil tank it’ll turn the oil milky white. Remove the old oil, dispose of it properly, add new oil, and start the engine. Let it run 15-30 minutes.
  • Wet carburetor – drain and clean the carburetor. Allow to fully air dry.
  • Wet air filter – clean the filter and let fully air dry.
  • Wet lawnmower blades – allow them to fully dry. Do not mow in the rain or mow wet grass.

How Water Can Get Into The Lawnmower Gas Tank And What Happens

What can get in your gas tank if you refill in the rain, mow in the rain, have leaks in the tank due to corrosion, the gas cap isn’t fully on or fully sealed or is faulty, or you have leaks in the gas line.

Even small amounts of water in the gas tank can cause big problems. At a minimum you’ll notice performance problems. In the worst case where water sinks to the bottom of the gas tank it can cause corrosion and eventually lead to leaks in your gas tank and possibly fires during use.

Common performance problems include:

  • Hard Starting
  • Running and Stopping
  • Sputtering or Surging

How To Deal With Water In The Gas Tank

To deal with water in the tank do the following:

  1. Drain all the fuel from the gas tank, fuel lines, engine, and carburetor.
  2. Add new gas/oil mix as required by your specific lawnmower.
  3. Run the lawnmower for 15-30 minutes. Check for the performance issues above. The hot engine should remove most of the remaining moisture if any. You shouldn’t see any hard starting, stopping issues, or surges.

Can I Leave My Lawnmower Outside?

No, you should not store your lawnmower outside uncovered. Yes, you can leave it outside temporarily while you eat lunch or need a break from mowing a large yard. Yes, you can leave it outside if you have no garage space for it. Make sure you use a good waterproof lawnmower cover.

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