How to un seize a riding lawnmower engine

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One may face many technical problems from time to time if he owns a riding lawnmower. A seized lawnmower engine is, however, one of the rarest of problems. If you do not want to take your Lawnmower to the mechanic because you fear that he might charge more, don’t worry. This blog will help you distinguish the damaged parts, replace them, and test them, all at a home scale.

A lawnmower engine is usually a sturdy component. A seized engine is usually due to the piston and rings sticking in the bore. With the help of some freeing fluid or cleaner, this problem can be solved. However, there might be other contributing factors to this too. Here we take you through them all.

How to un seize a riding lawnmower engine:

  • Step 1: Remove the spark plug
  • Step 2: Clean the combustion chamber with some cleaner
  • Step 3: Open the head and gently tap the piston cylinders
  • Step 4: Check the motor oil
  • Step 5: Test the blades and close all the components

We shall provide in-depth details of the steps mentioned above, like what sort of tools you need and any complexities you might face. Please stick with us as we go through all the potential issues and troubleshoot each of them.

Steps to Un Seize a Riding Lawn Mower Engine:

A riding lawnmower engine may get seized after you de-winterize it due to such distant usage. The seized engine may be due to the parts that are stuck or due to the machine’s absence of motor oil. The procedure below explains all the necessary steps to deal with the situation.

● Step 1: Remove the spark plug:

Whenever a defect occurs related to the internal parts of a lawnmower, removing the spark plug is the first step. The spark plug is removed before cleaning the rest of the parts for two purposes. One is so that no accident occurs when one is pulling and cleaning the cord. The second is to clean the spark plug itself.

To do this, tilt the lawnmower body to a side so that its side now faces the roof. With the help of a plier, unscrew the spark plug because it may be hard to remove it by hand (seized up chamber). Now, using a feeler gauge, you may check the gap between the spark plug terminals. Compare it with manual reading. Now, either clean the plug or replace it.

● Step 2: Clean the combustion chamber with some cleaner:

Through the removed spark plug hole, you can access the piston cylinders and the combustion chamber. You can quickly get aerosol sprays like “Blaster PB” or “WD-40” from a local hardware store. When you buy them, do get yourself a pair of safety gloves as these might be toxic to spray, hence injurious to health. Now, through the hole, flood in an available amount of the cleaner spray and let it rest there for a couple of hours at the least.

The cleaner spray acts as an anti-rust and lubricating agent. It removes the clog built up in the chamber. After a few hours, let the cleaner fluid drain out from the spark plug hole. Now, try to move the blades manually. Make sure that while rotating them, they should be rotated in their natural directions. You will feel lesser resistance to the movement now.

An additional step can be to pull the cord and see the blade’s rotation. This may further give some idea about the extent of seizing in the engine. Pulling the card will produce little motion in the lawnmower blades, a sign for a seized up engine.

● Step 3: Open the head and gently tap the piston cylinders:

Sometimes, only using a cleaner doesn’t solve all of the problems as the riding Lawnmower may have been idle for a longer time. In this case, remove the seat to expose the head of the engine. Opening the head with a screwdriver or wrench will allow you actually to see the piston cylinders. The engine may be blocked and may require an internal push start.

So, hit the piston head preferably with a wooden hammer. Tap it gently as it moves down. This pretty much solves the problem. Besides, check the piston rings, lubricate them. Check for any damaged seals, take no risk, and replace them. Clean the cylinders and remove any dirt or debris that has hardened up and is stuck. Throw in some cleaner spray to moisten the dirt and clogged up the oil. Clean it and let it dry for a few hours.

● Step 4: Check the motor oil:

We have already taken you through the basics. These were easy to solve. Now, a more complex issue that may require more of your focus is here. In all types of seized activities, the one that is caused by running the engine on an insufficient motor oil spray is the most serious.

Through the removed piston head, disintegrate the crankshaft. Same as before, using a wooden hammer, give the cylinders a strike to thump them out. Also, rotate the crank. This helps remove the crude oil that got stuck up in the moving parts. Use a cleaner to purify them thoroughly.

Remove the connecting rods and seals. Clean them too, as crude oil may still be stuck there. Give the insides a thorough washing. You can use petrol to wash it too. Now, let the engine bask in the sun and dry up naturally. Add lubrication to each component as you close up the casing and side by side, give the lawnmower blades a gentle thrust to make them move.

● Step 5: Close all the components:

After all this day long hustle, most of your technical work is done. However, closing all the components is the essential key for prolonged safety from damage. After all the parts have been lubricated and dried up, conceal them as they were taken out. Ensure the seals are tight, the crankshaft is fixed, and piston cylinders are’ t free. Close the head and fix the seat back in its place. Add new motor oil to your Lawnmower. Remove the old crude fuel. Add new fresh fuel, preferably with some anti-clogging agents mixed in. For a week on, use the mower gently and regularly so that engine gets back to its full potential.

Even if, after all these steps, the blades aren’t softening up as much as they should, it is time to call in an expert.

Related Questions:

1) Why should I use a wooden hammer or wood to strike the piston cylinders?

The combustion chambers are quite sensitive parts in terms of dimensions and sensitivities of pressure, are, and volume. A regular hammer, if used to thump the cylinder, may cause the cylinder to disorientate. At the very least, it can cause a dent in the cylinder or piston due to its rigid nature. Deformities can cause a change in the critical pressure or volume of rotating machines, which can be very dangerous.

A wooden hammer, on the other hand, is rigid and flexible at the same time. You may have observed that all denters use a wooden hammer to remove the dents too. This allows them to give a considerable power strike keeping the flexibility and geometry intact.

2) How can you tell if your lawnmower engine is seized?

To tell if a lawnmower engine is seized, you have to follow through a few steps. Start by removing out the spark plug to expose the channel to the combustion chamber. If a lawnmower with a removed spark plug still jump-starts, its valves may be worn out and hence, need replacement. However, if the engine doesn’t run and the blades are rigid and don’t turn over, it is seized. A seized lawnmower engine has locked cylinders, blades, and pistons.

3) Why removing the spark plug is necessary?

When operating on a riding lawnmower with sharp blades, precaution is a must. While cleaning, one has to clean the combustion chambers, piston cylinders, and valves. Sometimes, even the cord needs maintenance, so it has to be pulled. So, as a safety measure, it is advisable to remove the spark plug before any Lawnmower action to keep away from any harm.

Final Remarks:

For those who love their hobby of gardening, a lawnmower is the best buddy one must-have. However, after long gaps or after de-winterization, its use may pose some problems in engine activity seizing up. A seized engine doesn’t mean the machine’s death, but it sure affects its life if not addressed. Following the steps mentioned above in definite order, you can efficiently deal with this issue. It may seem huge at first glance, but following the guide will help you step by step. Even after all these steps, your Lawnmower fails to work correctly, and it is better to take it to a mechanic. Happy lawnmowing!