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How to tell if a riding lawnmower engine is seized?

One morning you try to start your lawnmower, but it doesn’t. Instead, it makes grinding and tricking noise. Your mower switches off, and its blades get stuck. If you try to rotate its blades manually, they won’t. All this tells you that your mower engine has seized. As the engine is a vital part of your lawnmower, if it is seized, you will not be able to start the mower.

So what is the leading caused that seized your engine and made it difficult to start? And what can I do about it? This blog will help you look into the problem. The principal factor is the lack of or insufficient oil supply that makes the lawnmower engine’s internal parts to seize. But there are other factors that we will further explain and how to fix them in this article.

How to tell if a riding lawnmower engine is seized:

  1. It sounds rough.
  2. Hard to start the engine.
  3. The blades are stuck.
  4. The piston and cylinders won’t move.
  5. The oil will be deficient.
  6. The fuel quality will have deteriorated.

This is a lot to take in, but there is nothing too hard for you to do at home. If you follow our simple steps, you will most likely find the cause behind your lawnmower engine seizure.

Steps to Follow:

This article provides a detailed list of the most probable indications if your lawnmower engine is seized. The components to be checked and the probable causes and solutions are given below.  

Step 1: Check the sound:

A lawnmower sure does make a loud noise while operating. A seized engine means an engine that is stuck. Most probably, if your lawnmower engine is seized, it won’t even be able to start at all. If you succeed in starting your mower in a scarce scenario, it won’t stay active for long. The little action it has left will make huge grinding noises as if its parts are colliding. A huge gurgle with an immediate shutting off of the mower engine is the first indication that the engine is seized.

Step 2: Start the engine:

On the off chance that your mower had seized up and you weren’t aware, you can face two scenarios. When you try to start the engine, it starts up; it makes up the same noise as mentioned above and shuts after a while. In the second scenario, you will be unable even to start up the engine. In this case, you will feel the tightened cord, the stuck up blades, and dead engine that gives no sign that it is alive. In this case, no matter how much you pull on the cord, you won’t be able to start the engine. The engine needs much work and complexities to be dealt with before bringing it back to life.

● Step 3: Check the blades:

As we have mentioned before, a seized lawnmower engine will have stuck blades. What does it mean when one says the blades are stuck? Stuck blades refer to the blades’ jamming, which is too hard to rotate even by hand or some tool. The blades get fixed in position and are unable to move. This is due to some internal jamming of components that lock up. Stuck blades will never allow the lawnmower to start; instead, they will backfire, shutting down the engine. Much has to be done to bring them back to action.

● Step 4: Check the piston cylinders:

A lawnmower engine that is seized up has some internal jammed parts as its primary cause. The jammed parts are primarily its pistons that get stuck into its cylinders. The causes can be many. Sometimes, the engine seizes up if it was exposed to a puddle of water. The moisture from the water can make contact with the scorching engine. This can cause the engine seals and valves to explode. The damaged seals will cause the piston to become free. They can cause oil to waste away. An unlubricated piston will get stuck up in the cylinder. If the main combustion chamber gets seized up, there is no energy production, let alone the different components’ free movement.

To check them, remove the spark plug as the first step. This is a precautionary step. Next, remove the head of the engine after removing the seat. This will expose the pathway to the engine assembly. We would suggest that you do these steps only to find the cause and leave the experts’ actual technical work.

● Step 5: Check the oil level:

The second major cause for engine seizure is the oil shortage in the engine. Decreased oil levels in the chamber can cause significant issues. If the oil, lubricating the moving pistons vanishes, the pistons jam due to the lack of lubrication. So, you need to check the gas tank and chamber for oil levels.

Before you get cracking, get ready with the gas container. Now, detach the fuel line attached to the carburetor. Put the gas container below the tank and drain the gas out. When the tank will be empty, use a flashlight to check for debris and beads of light that will show cracks or holes. Use a baster to remove slack debris. After you have removed the debris, now check the oil gauge. Also, as mentioned in the previous step, check that the cylinder walls are well lubricated.

A deficient oil level will indicate a seized engine for sure.

● Step 6: Check the fuel quality:

If the lawnmower engine is seized, it will also have low quality fuel in its chamber. This is an additional indication, not the primary one. The crude oil in the chamber gets clogged up in the chamber. This can cause improper combustion that causes debris to be stuck up in the chamber. This can lead to the failure of piston working.

Check the following video. It will help you visualize the causes of the engine seizing as the person troubleshoots his mower:

Preventive measures:

Following precautions should be kept in consideration while cleaning opening up different parts of the mower:

  • The necessity of gloves: Use gloves for extracting debris, grass, and old dirt from the blades
  • Avoid Personal damage: Handle with care to avoid cuts and any delicate harm from the sharp blades.

Do not overfill the oil tank. Usually the manufacturer shows the max and min level so you can fill it without putting in too much. If you can not find it check the manual. Oxidation of the internal components of the engine will make the mower impossible to start. Maintaining proper oil level increases the durability of the engine. 

Frequently asked questions:

1. What does a seized engine sound like?

Though, a seized engine sound predicts the forthcoming issue. When the problem is at the initial stage, you will hear a light drumbeat, hitting or bumping sounds while starting the lawnmower. While at the last stage, you will hear the hammering and bashing sounds from the lawnmower. The flow ends with a grinding noise at the end before the total seizure.

2. How to Un seize an Engine that Ran Out of Oil?

You need to follow these steps:

  • Step 1. Disassemble. Pull apart the cylinder head and crankshaft in case the oil penetration does not work.
  • Step 2. Inspect the Damage. No matter what caused your engine to seize, both the cylinder and piston are damaged.
  • Step 3. Check the plugs. Do not fail to recall the connecting rods & wrist pin bearing.

3. Why can’t I pull-start my lawnmower?

The crankshaft is associated with the blade shaft on your recoil, so if the pull cord is jammed, it could be because something is hindering the movement of the blade. Disconnect the spark plug for safety, and then look under the deck.

4. What does it mean when your lawnmower cord won’t pull?

The connection is direct in the rotary mower, which predicts that there are no gears or belts. If the drawcord does not release, it could be twisted or jumbled up, but it’s also possible that something is discontinuing either the blade movement or the engine crankshaft from moving.

Final remarks:

Categorically, it is not crucial to identify the cause behind the riding lawnmower engine seized. Regular repairs keep the mower engine in a good state. I hope that from this article, you will get a vibrant, admirable & sharp idea to visualize the causes behind your lawn mower engine seizure. The processes, as mentioned earlier, will help you identify the causes of the problem. You can get to know which part is responsible for the problem created. However, these are only the steps to help you inspect the different components to pinpoint the error. To un seize the engine, follow our other article, which gives some easy to follow simple steps. Taking care of these problems can hold you back from this disturbance and provide a lawnmower engine’s prolonged existence. Happy lawn mowing from our side!