Has it ever happened to you that you are mowing your lawn peacefully and then you stop for a minute for whatever reason it may be and your mower won’t start again because it’s too hot?
Yeah, you are not the only one a lot of people have this same problem where your mower just refuses to restart when you stop for a moment in between including me. Many say it’s overheated or too “HOT” so it causes this problem.
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Reasons a Lawn Mower Won’t Start When Hot
Now let us observe what actually happens to your lawn mower when it’s too hot, most likely it occurs due to a failing coil but there are other possibilities as well such as:-
- The plug of the mower may be faulty
- The engine may be flooded
- The level of the oil may be low
- The engine may be overheated
- The wire of the plug may have some problems.
- The auto choke may have some fault in it.
- The carburetor may be having some problems.
- The compression may not be right.
- The valves may have a fault in them.
How to Fix All These Issues?
Now lest see how to solve these problem by yourself, firstly we will look into problems that are easy to solve then we will go into deep and complicated stuff.
Time needed: 3 minutes.
How to Fix a Lawn Mower that Won’t Start When Hot?
- Check the oil level in the lawn mower.
This may not occur to you but some mowers have this in built settings in them that does not let them to start if they have low oil level in them. So that the engine does not reach a level where the oil level is critically low so it does not harm the engine.
To avoid this problem check the oil level regularly whenever you refill your gas and also keep checking it regularly. Many movers take up from empty 6lt of 5w30 or 10w30. But be careful not to fill up the tank very much because it can also damage the engine.
- Check the Spark Plug.
As we all know that the lawn mowers take up a lot of electricity and some bad quality plugs can get over heated and cause problems due to their low resistance to voltage. The hot plug can cause start failure.
To avoid this situation one should check know the correct plug code so that they can buy the plug of the right power. It is also useful to have extra plugs of good quality at your home do that you can change them when needed. Sometimes only changing the plug can solve the problem and you can start you mower.
If still, your lawn mower is not fixed, please examine the coil.
Examine the Coil
Coil is a set of copper wire wounded around a metal core also known as winding. It produces voltage when the engine completes one revolution. The coil is just above the cylinder and does a lot of work and it gets exposed to high temperature. Most of the coils have two different winding primary and secondary coil.
How does a Coil work?
There is a magnet attached to the crank shaft on the top of the flywheel, whenever the magnet passes through it produces voltage in it. There is also a transistor in the coils that prevents the spark by opening and closing the circuit.
Searching for the ground the voltage travels along the plug which provides it with a perfect pathway and when it finds the ground the positive voltage jumps from the plug to the ground and sparks occur.
This procedure only takes just milliseconds and it is repeated on every revolution.
The engine of the mower can be shut down by stopping the supple of electricity that is provided by the plug. This can be done by providing a much shorter path to the coil to ground and when this path is supplied the voltage passes through that path and the engine shuts down.
When the wire is changing the ground source the engine will not wor or it will rum intermittently.
The coil is not service able so one should always keep checking it so it does not have any problem. When ever you use the mower the temperature of the coil rises and at higher temperature there is more resistance to voltage so the coil does not work at high temperature and causes the mower to stop working.
And one should also keep in mind not to leave the mower outside or in a moist area because it is an electrical machine and electric appliances and water don’t go well, if you get water im the coil it will cause problems and thr mower will stop working.
MOWER REPAIR TOOLS:-
When one has spen this much on a machine one should also have tools to repair it for when it gets some problem so that they don’t have to spend on the repair of the machine.
How to Check Spark Wire, Coil Plug, the Bail Lever, the Plug Wire using “The Coil and Plug Test?
Now we will tell you how you can check the spark wire, coil plug, the bail lever, the plug wire the on and off button. There is also a special button for the plug spark which is known as the in line spark testing tool.
Spark Check Tools:-
The tools you will need for spark check are :-
- A new plug.
- Plug spanner.
- Insulated pliers.
- A person to help you.
First you will need you insulated pliers and with their help you must hold the plug against the metal part of the engine to ground it but be careful to do it well or it will cause misdiagnoses.
Now check the plug by putting a test plug in place to check for the spark.
Now the other person you called for your help, should try to start thr mower to check it as you will observe the spark plug.
If you don’t have a spark even after doing this process then you must have a faulty spark plug wire, plug cap or coil damage. If you have spark but still the problem remains then you may clean your carburetor.
PLUG WIRE DAMAGE:-
Plug wire can be damage by mice or due to old age or many other reasons.
If there are no such damages on the wire then you may observe the lever or the switch for any damage.
The bail lever should be tight in order to start the mower otherwise it won’t work. Observe your bail lever if it is not tight then adjust it by tightening it. Most of the companies have an adjuster at the handle bar.
The bail lever is attached to the engine brakes with causes the on an off of the engine. When you let go of the lever a brake block pushes the flywheel which slows the engine and which in turn causes the ground on an off switch to be activated. You should check that switch for problem too.
How to Replace the Coil?
If all the above mentioned things are okay and have no problem you should check the coils they may have some problem and they are easy to be replaced. If you don’t know how to replace the then don’t worry we will tell you how you can replace you coil yourself and in this way you don’t have to spend money on it.
First remove the bolts and plates on the connector wire. Each engine has its own different coils so one must check their engine type model before ordering.
Under the coil there is usually a push on wire connector which is called the coil control wire.
Although one may think that all coils look same but they are not same and they make a difference so one should be careful while ordering.
Ordering coils online is easy you only need to know your engine model.
Now you have to push the fly wheel and the coils together but you must be careful to leave a tiny space between then for that you can use any business card or cardboard paper an place it betwwen the flywheel and the coils and then push them together it will leave just the right amount of space between them.and when you have done that remove the business card.
THE ENGINE MAY BE OVERHEATED:-
An overheated engg=ine may be due to one of many following reasons and it can cause serious damage:-
- Lean running engine.
- You may be using wrong plug or furl.
- Air cooling fins may be damage.
LEAN RUNNING ENGINE:-
The engine which is lacking fuel is called a lean running engine or it may have alor of air for air-fuel ratio so there may be a vacuum leak or the air must be going into the carburetor which makes it over heated.
THE FUEL MAY NOT BE OF GOOD QUALITY:-
People usually make mistakes in choosing the fuel for their mowers including me. I also chose the wrong fuel and damaged my mower but now I have learned my lesson and want you people to learn from my mistake and not make it yourself. Mowers have small engines usually so regular gas or e10 ethanol is good for it and e15 an e85 are harmful for your engine as they burn hotter and they cause the engine to get overheated very easily.
FAULTY AIR COOLING FINS:-
So usually most of the companies have designed their mowers in such a way that they have cooling fins and major part of the engine is exposed to the atmosphere to cool it naturally but sometimes when we are careless we do not clean our engines and the dirt and old cut grass pieces get attached to it and cover these fines and don’t let them be exposed to the sir thus causing the engine to heat up.
The oil in your mower not only lubricated the parts in the engine but also to keep it cool so if you run your mower at the low oil level it will rise the engine temperature. The coils and plugs in the engine will also get problem and will not work when the engine gets hot.
IS IT GETTING FUEL:-
If your throttle is not adjusted correctly it can cause the engine to not start. Sometime it may have operator problems also.
Your mower may have an auto or manual choke. The choke is there to enrich the fuel engine that is why when the engine is hot it doesn’t start smoothly.
If you carburetor float needle is not working right it may cause problem also as it will supple slot of fuel when you stop your mower in between the fuels floods into the engine and makes it hard to start it.
If your engine is fitted with the priming bulb it will be hard to start and it will produce a lot of smoke and you will need to clean your carburetor or replace it.
But if you have a choke plate type then you can follow this process to solve this problem.
Firstly remove the air filter hosing completely and when you turn on the throttle the choke plate should be open.
This test will be applied either you have a coke lever or auto choke. The choke plate, when hot, should be open. If it s not open observe the binding in linkage.
The correct way to start a cool engine is to have you choke plate slightly covering/ closed. When the choke lever is being operated the choke plate must be completely closed.
REPLACING THE CARBURETORS:-
It’s common for carburetors to stop working and you can solve this problem by cleaning the carburetor but if even after that it still produces a lot of smoke then that is the time to replace your carburetor.
And don’t you worry about that also because we have an easy solution for that to you can go to Briggs & Stratton carbueretor. They have the most inexpensive carburators and they are easy to fit also so you don’t have to worry about your carburatoer not getting fit.