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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
Hi Mitchell, thanks for your suggestion, take it to a mower tech. Do you know how much they charge? Not less than $150. Why I should I take the trouble in carting and paying so much. I can buy a new one. I decided to throw it. Thanks for the discussion.
dajeva
That's understandable, @dajeya. I do apologise, but you've now gone through all basic troubleshooting, including an advanced step of cleaning the carburettor. At this point, you'd be looking at replacing parts in the hopes that it would resolve the issue and that in itself can be a costly exercise.
Mitchell
Hi Mitchell,
This machine does not have a primer to inject fuel to start the machine. How can it start when you pull the starter rope? Is there a automatic choke which inject the fuel when you pull the cord? if so where is it?
When I physically inject a little fuel into the carb through the air filter and start, it starts with 2 pull.
dajeya
Hi @dajeya,
A lawn mower without a priming bulb typically uses a gravity-fed fuel system or a diaphragm carburettor to inject fuel into the combustion chamber for the initial ignition. In both systems, the engine's mechanical action, such as pulling the starter cord, creates suction that draws fuel from the fuel tank into the carburettor and then into the combustion chamber, enabling the engine to start.
A blockage in the fuel or return lines could prevent the fuel from being drawn to the carburettor.
Mitchell
Hi Mitchell,
My carb is not a diaphragm type. If there is a blockage in the fuel line, the machine will not keep running once it starts running. How suction is created to pump fuel into the carb when you pull the cord? What is the mechanism here? What is the function of the black tube that is running from the rotter to the air filter housing?
dajeya
In a lawn mower with a non-diaphragm carburettor, the suction needed to pump fuel into the carburettor when starting is generated by the engine's intake stroke. When you pull the starter cord, the engine's piston moves downward, creating a vacuum in the combustion chamber. This vacuum draws air in through the carburettor, which in turn draws fuel from the fuel tank through the fuel line and into the carburettor.
The black tube running from the carburettor to the air filter housing is likely the crankcase breather tube. Its function is to vent gases from the engine's crankcase, allowing them to be drawn into the carburettor and burned in the combustion chamber. This helps to prevent pressure buildup in the crankcase, which could lead to oil leaks or other issues. Additionally, it helps to reduce emissions by ensuring that any unburned gases are circulated back into the engine for combustion.
Mitchell
Hi Mitchell,
Thanks for your reply. What you suggest is, there is insufficient vacuum created to draw air to get fuel into the carburetor to start first. What is the solution please?
Regards
dajeya
@dajeya
If I read correctly, you stated if you manually placed fuel into the carburetor the mower fires up... thus you have a fuel delivery issue.
how is the fuel filter in the tank (they can become blocked)?
how are the fuel lines (fractured lines lose vacuum/pressure)?
how is the filter (a clogged air filter will stifle the combustion process)?
have you tried starting (normal process) with no air filter?
Hi Mitchell,
Yes I said, when I inject little fuel in the carb it fires.
There is no leakage in the fuel line, the air filter is clean. I removed the fuel tank and cleaned. If there is fuel block, then how it continues to run once it starts?
When I removed the carb for cleaning, I used carb cleaner at the fuel entry point and it was coming out with no blockage.
Now what to do?
Regards
dajeya
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