If your lawnmower comes with an automatic choke function, you may be wondering what this choke does in your engine and how it differs from a manual one.
The automatic choke in a lawnmower is important to regulate the fuel to air ratio on your mower when you start it up, this choke automatically turns on your lawnmower when you are using it from a cold start.
So as we can understand more about the auto choke on your mower and how it works, as well as how to adjust it, we have put together a short guide below that will give you all the essential info.
Let's start with what an auto choke is. We briefly explained above, the automatic choke is the part of the mower which allows your mower to turn on from a cold start or when the engine hasn't been used in a while. This choke is used on all vehicles with an engine that has a carburettor.
So in simple terms, the auto choke on your mower aids your mower in starting no matter how cold it is or how long its been since you turned the engine on.
The auto choke is automatically activated when you switch the ignition of your mower on, from a cold start, the carburettor on your lawnmower will need more fuel than air to start-up, meaning that this choke will close slightly to block some of the air from entering the engine.
When the engine of your lawnmower becomes warm and reaches its ideal temperature, the choke will open up to allow a normal ratio of fuel to air.
On older lawnmowers, you may still find that they have a manual choke function, which would require the operator of the mower to pull the knob of the machine to activate the choke then push it back in when the engine on the mower has started and is running smoothly.
An automatic choke will do all this work for you and operates by using power from the mower's battery. You can easily see whether or not your lawnmower has a manual or automatic choke by looking to detect if there is a choke indication by the throttle of the mower.
Because technology is great, automatic chokes allow us to forget about whether or not we turned the choke on or off on our mower.
But you might be wondering, what would happen if the choke was left operating on a mower while it's in use?
Well, number one it would probably ruin your spark plugs over time and you would waste a lot more fuel, due to the fuel to air ratio being richer in your engine.
Too much fuel in your mower's engine would eventually cause it to stall at some point too and may require you to drain the excess fuel from the engine of the mower which is a long yielded process. This is why auto-choke was invented, so as you wouldn't have to worry about forgetting to turn the choke off and to make starting your mower less hassle.
Most auto chokes work smoothly on newer lawnmowers with no issues, but some common problems can occur such as your choke becoming stuck or the lawnmower only starting when the choke is set on.
Now, if the automatic choke on your lawnmower has become stuck, it may need some lubrication as rust is likely to build up around the choke area on the engine, your auto choke may have potentially failed too, which means you would need to replace it with a new choke.
If your lawnmower is only starting when the auto choke of your mower is on, that means you could have an issue with the carburettor of your lawnmower such as a blockage, meaning you would need to get the carburettor looked at by a professional or clean the engine yourself.
So as you can keep your auto choke running efficiently, we have listed out a couple of tips below about maintaining it.
As we already know, the automatic and manual choke help your mower start in cold weather, but what happens if your choke is working fine, but the lawnmower still cannot start?
We have listed briefly a few other causes which would be worth troubleshooting if your mower is not starting in cold weather.
Is an auto choke or manual choke better on a mower?
This depends on how well you know mowers and engines, an auto choke takes out the hassle of having to manually start the choke and stops you from worrying about remembering to turn it off, however, an auto choke is likely to have more issues than a manual one and can't be adjusted or fixed as easily as a manual if something goes wrong.
How long should I wait for my mower to warm up?
You don't need to wait for your mower to warm up as it should be ready to use pretty much straight away after you turn the ignition.
What do I do if my engine is flooded from a faulty choke?
If too much fuel has been let into your mower's carburettor you can try draining it and letting the air filter dry, if the engine still isn't working after this then you will need to take it to a professional to get fixed.
To conclude, mowers with auto chokes allow you to start up the mower with no manual interference and permit your engine to get the fuel it needs before it warms up, helping it start smoothly no matter the weather conditions.
Depending on the mower that you buy, the machine will likely come with either a manual choke or an auto choke, for manual models you will need to push a valve multiple times to allow the mower to start properly.