My Trimmer line need replacement and I am not sure if this 3mm line below actually fits my trimmer line? I am using Ferrex trimmer line. If yes, how do I replace with the new line?
Hi @gavin16,
Do you have another part that clips into your trimmer head? There is usually a spool that clips into the grooves in the base of the trimmer head. It will have two holes that the line feeds through. The diameter of these holes will determine what line can and can't be used.
As long as the line can comfortably feed through the holes in the spool piece, then you should be fine to use the line. 3mm is a fairly standard size for home use trimmers, so I would be surprised if it did not work with yours assuming you still have the spool.
Without the spool, your trimmer can't function as intended. If you can't find it, then you may have to look at replacing the trimmer head or purchasing a new trimmer.
Once you have the spool piece, it is usually just a matter of winding the line around it, then feeding it through the holes.
Let me know if you have further information or questions to add.
Jacob
Hi Jacob
Here ia the other part of my trimmer
Your image hasn't come through. Can you try again? If you have any trouble, feel free to send it through to workshop@bunnings.com.au and I can upload it for you.
Assuming it is the other side of your trimmer head, have you measured the holes in it?
If they are larger than 3mm, then you shouldn't have any issues using this trimmer line.
It's come through now.
You need to check the width of the opening here -
This will tell you if your line can be used in this trimmer head, which judging by the photos, should be fine.
Then, you can follow this video - Cheetah 2 stroke Trimmer - Loading the Trimmer Line from our supplier Cheetah, to load the line on to the spool.
If you have any issues, please let me know so I can assist further.
Evening @gavin16
How did you get on with the Ferrex trimmer line?
Hi @Noyade , I managed to roll the 3mm line into the trimmer head despite finding it a bit hard & thick. Then I checked & realized that my trimmer's recommended line was only 2 mm. I tested it by running the trimmer and it seemed to be working fine even though when engine running the head seemed to be struggling a bit to run freely as compared to my previous line. The line seemed to pass through both holes as well.
Can I continue to use them?
The load on the motor to rotate the heavier line through the grass would be higher, but I can't imagine it would be so drastic going from 2mm to 3mm line. In saying this, if you were using it and your trimmer seemed to be really struggling and was cutting out or overheating, then you should cease use immediately and swap over to the recommended 2mm line.
It's always best to stick to the manufacturer's recommendations with stuff like this.
Let me know if you have any further questions.
Hi @gavin16
"struggling a bit to run freely"
Sorry Gavin, I'm not entirely sure what you mean by this?
I went with a Ferrex line and 'upgraded' from the green 2 mm to the 'licorice twist' 2.4 mm. The big difference was a reduction in noise, I reckon by 60%, so much so I thought there was something wrong. But I'm now using a 1150 W 240V machine now - not 2-stroke. I don't know why the profile produces less sound, but it works fine.
Thanks for sharing, is the 240V engine much powerfui than 2 stroke? what I meant is when we start the trimmer without pressing the trigger, last time the head will turn slowly in a free run. now, it occasionally stop and not as "free run" as last time.
Hopefully @Noyade can share his experience, @gavin16. In my opinion, a 240V machine of around 1100W is probably 80-90% the power of a two-stroke machine. The head moving when not under throttle is not a concern, as it is likely caused by the heavier gauge line.
Regarding your original question, you can generally go about 0.5 mm above the manufacturer’s recommendation. For your trimmer, 2.5 mm should work fine, while moving to 3.0 mm is outside the machine’s intended design. This can lead to a couple of issues. First, the line may be more difficult to load, and the auto-feed may not function correctly. Second, you may notice a loss of performance. Two-stroke engines perform best at higher RPMs, and the heavier line increases the load on the engine, which can prevent it from reaching the range where it delivers maximum performance. Please let me know if you have any questions.
Mitchell
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