Too much oil in lawnmower

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A common complaint among owners of lawnmowers is about too much oil in lawnmower.

Below we’ll teach you how to prevent this and protect your machine from serious problems like ruining the motor or bending the crankshaft because of overfilling your mower with oil.

Plus, we explain how to drain oil from lawn mower.

Let’s get started:

Too much oil in lawnmower : What it means for your mower

You and I know that just like a vehicle engine, a lawnmower engine requires oil for reasons such as proper lubrication of the many moving parts and to keep it from overheating.

But putting too much oil is detrimental to the mower in a variety of ways yet this is a detail that users often fail to pay attention to.

It’s also possible that you may have accidentally poured an excessive oil amount during engine maintenance.

Either way, you should be very worried if you notice the lawn mower dripping oil because of overfilling.

Here is why:

What happens when you put too much oil in a lawn mower engine

·         The engine is affected and might no longer perform as expected

The first thing to fall victim to overflowing oil is the engine itself.

And a multitude of things can go wrong here.

For example, because of oil leaking to parts of the mower engine that are never intended to come into direct contact with oil, you begin to experience annoying problems including the lawn mower refusing to fire up.

·         Mower overheating

Another trouble that tends to emerge this time if the ‘foam’ in the oil (oil often foams when flooded) blocks it from being distributed to some components is overheating.

The outcome is a failure to effectively keep them continuously lubricated as the various pieces continue scraping against each other triggering heat buildup (friction causes heat).

Still, some of these elements may be receiving more oil than needed for lubrication forcing the engine to work harder.

This, in turn, provokes overwhelming heating in the engine. 

Overheating carries a huge risk and can bring tons of damage (your mower is already suffering thermal stress from the blistering summer heat buddy!)

·         Crucial parts are damaged

If this condition lasts, some internal engine parts will probably be destroyed beyond repair.

For example, those being consistent rubbed on will be broken including the pistons.

The crank is not spared either and could be bent resulting in the mower experiencing disconcerting vibrations as you mow.

Seals and gaskets might also be terribly damaged necessitating replacements as could the motor when there is too much oil in lawnmower engine.

At the worst, the engine can be permanently ruined in cases where the crankshaft repeatedly strikes the bursting oil while the engine is still running.

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Signs that there’s too much oil in lawnmower

As you have learned, this is not a matter to be treated casually and it’s important to be on the lookout for symptoms of your mower having an oil overfill.

Now, there are a couple of warning signs as summarized below:

  • White smoke – the muffler emits white smoke when the engine is covered in oil (the engine is battling to burn the extra liquid by now).
  • Oil in lawn mower carburetor- the surplus lubricant could also flow towards the carburetor the moment you tip the mower on the sides or even when mowing on hilly terrain.
  • Oil coming out of the mower’s exhaust- there is a good chance that the engine is swimming in oil if you’re seeing this.
  • Oil drops on the air filter (if installed)- this is another sign of the mess.

But the foolproof method of establishing the truth about the issue is by checking the level of the liquid on the dipstick (while the mower’s engine is cold).

And don’t play the guessing game regarding this- refer to your owners’ manual for the recommended oil mark for your mower brand.

How to rescue the situation

The immediate remedy is to drain the excess oil from the mower. Have a look at the best oil drain pans available in the market today.

The good news is that you don’t need to hire a professional for this task except where your mower is already in a bad state.

Find the steps next.

How to drain excess oil from lawn mower

Here is how to remove excess oil from lawn mower (general instructions):

  1. Wipe all that area near the crankcase (use a rag). You don’t want smudged debris plunging into the crankcase on opening the drain plug.
  2. Tilt the deck and place some newspaper and an oil container to collect the oil beneath the mower.
  3. With a socket wrench, remove the plug (twist counterclockwise) and allow maximum oil to drain (check your manual for instructions if stuck).
  4. Return the drain plug and tighten suitably after emptying oil from lawn mower.

Tip: For Briggs and Stratton overfill oil (and some few other engines), drain with the oil removal kit if uncomfortable doing it manually or unable to figure out how to take oil out of a lawn mower on your own. 

How to drain gas from riding lawn mower.

How much oil does a lawn mower take?

Rather than speculating and jeopardize your engine, it’s wise to research the correct volume of oil to add to the mower.  

And the best place to get a concrete answer is your engine owner’s manual (or from an expert).

That’s because it depends on the mower type and the size of your engine.

For instance, walk behind engines (18–22 inch) consume about 20 ounces.

Likewise, you can load 1–2 quarts in most riding mowers.

And so forth.

Final thoughts

Make it a tradition to check the oil level prior to starting the mower’s engine- it helps you discover an oil overfill or leakage before it’s too late.

In a related note, always use the manufacturer’s endorsed oil type- a wrong oil type reduces lubrication and could shorten the engine life.

Lastly, if you own a high-end mower, find out if the maker provides a Bluetooth app to jog your memory about changing the oil (when due).
It’s can save you a pretty penny in the form of a costly repair bill because you are stuck with bad oil.

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