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Lawn Mower Troubleshooting


Simple Lawn Mower Troubleshooting on Lawn Mower Engines

One of the most irritating things for any lawn mower is the problems that one runs into with the machine.

It is one of toughest machines you would have, but it is also the one that goes through the most abuse too, so problems are bound to occur.

The best solution to these problems is to take care of them yourself as much as possible.

To prevent lawn mower troubleshooting, you can do it a lot simpler if you have the right cheat sheets to isolate the problem. Once you know the problem you just need to get the right solution and using your Owner’s manual as reference you can solve the problem.

Here are a list of common problems and possible solutions to your lawn mower troubleshooting problems related to engine

Engine starting problems

The most common reason why the engine would not start in a relatively new mower is lack of fuel or water in the fuel.

In either of the cases the engine will not start properly. The other problem could be that the fuel injecting valve of the engine is choked.

You need to clean this to get the mower working properly. Over choked carburetor or improperly fitted carburetor are other reasons when you may find it hard to start the engine.

Another reason why you are having problem with starting the engine would be problems with the electric circuitry. The spark plug may not be functioning properly, the battery may be low or there may be some issues with the wiring. You need to check for these standard issues.

Lastly, refer to the handbook to find more tips for your specific model too.

Engine does not run for long

This is another common problem that happens due to lack of fuel.

The engine may start properly but will die out almost immediately.

This is standard when there is no fuel or the inlet valve is choked. Even choked carburetor can cause this problem.

Engine makes weird sound while idling

This can be observed when the engine seems to make unnaturally loud sound when it is idling. Sometimes you could hear a surge in the sound too.

All these are clear indicators of a very dirty carburetor or problem in the ventilation of the engine.
The ring or the inlet could have some lawn debris stuck to it. Clear this and things should come back to normal.

Very prominent engine vibrations

Typically, this will not happen in a brand new mower, but is common in a recently fixed mower. The reason for this is pretty obvious, incorrect reassembly of the mower.

Generally, when people fix back the mower after dismantling it, they do not realign the parts properly.

If the engine itself is not align properly and the aligning screws are not fit in correctly, it will vibrate. Other sources of vibration include loosely fit blades, bent crankshaft and improperly fitted counter balance shaft.

Mower efficiency is poor

This is observed when you feel like the blades are moving fast enough and the power from the engine is low.

Lawn Mower Troubleshooting

This happens with the fuel injection into the cylinder is not properly, may be the injection valve is choked.

Sometimes the ignition system is not timed properly to deliver maximum power, or the air filter could be clogged with lawn debris.

These can affect the engine power too. Problems with the pistons, crankshaft and other mechanical parts would mean that the transfer of power from engine to the moving parts is not optimum.

Oil spillage

This is generally rare in mowers but if the breather system or the pistons are faulty, you could have the crankcase passing the oil.

Faulty pistons due to excessive wear are one of the primary reasons for this problem.

besides this a faulty breather system is also a common cause for this. The breather system basically creates a vacuum or low pressure to ensure that the oil does not enter the combustion cylinder. If this system is clogged or broken down you could see the oil spilling around and leaking.

Overheated Engine

This is typically a problem when the ventilation system of the mower is clogged or when the mower is overloaded.

A clogged ventilation system could mean the inlet or cooling fins of the engine are blocked.

Other times you are just pushing your mower to the limit and that is causing it to overheat.

Other issues could be lack of enough lubricating oil. This would mean that the pistons are moving without enough oil and this will easily overheat the engine in no time.