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I have a Gardenline essential lawn mower. It is not firing. This does not have a primer. I cleaned the caburator and tried . Still not working.. I think fuel is not injected into the chamber. In a machine without the primer how, how the fuel is injected for initial firing?
David
Welcome to the Bunnings Workshop community @dajeya. It's wonderful to have you join us, and many thanks for your question about starting a lawnmower.
A self-priming lawn mower typically uses a diaphragm carburettor to draw fuel from the tank into the engine without a primer bulb. When the starter cord is pulled, the engine creates suction, creating a vacuum in the carburettor. This vacuum pressure draws fuel from the tank through a fuel line, mixing it with air and delivering it to the engine for combustion, simplifying the starting process without the need for manual priming.
How old is the fuel in the tank? If it's been sitting there for more than a year, I'd replace it with fresh fuel. What does the sparkplug look like?
Please let me know if you have any questions.
Mitchell
And how old is the fuel @dajeya?
The black hose you're referring to is likely the breather hose. It's a component designed to allow air to flow into the carburettor or air filter housing to maintain proper air pressure within the system. This helps prevent vapour lock and ensures the smooth operation of the engine. If the breather hose becomes damaged or disconnected, it can lead to engine performance issues.
Mitchell
Hi @dajeya,
In the choke mode, the butterfly valve at the front of the carburetor should indeed be closed to restrict airflow, enriching the air-fuel mixture for easier starting, especially when the engine is cold. The butterfly valve at the back of the carburetor, often called the throttle valve, should be in a partially open position to allow a small amount of air to enter the engine.
As for the governor's function in the starting process, the governor typically doesn't directly affect the starting process or move. Instead, its primary function is to regulate engine speed to maintain a consistent and optimal operating RPM under varying load conditions. The governor achieves this by adjusting the throttle position in response to changes in load, ensuring the engine runs smoothly and efficiently. Once the engine starts and begins to operate at higher RPMs, the governor will start to regulate the throttle position to maintain the desired speed.
Mitchell
The first thing to verify when troubleshooting a mower is how old the fuel is @dajeya. How old is it?
Mitchell
If it's within a year old, @dajeya, it should be fine. Anything older than a year, and I'd swap it out for fresh fuel.
Further testing would require a check for spark. If you are getting a spark but the fuel isn't wetting the plug, you'd likely need to take it to a service centre and have a technician look it over for you.
Mitchell
