Letting line out... Bump knob requires a slam!

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Just bought the 15" string trimmer.  The manual says all I need to do to release more line is by "lightly tapping the bump knob on the ground".  This is not working as the manual says.  I have to slam it down on the ground to get the line to come out and then it only works sometimes.  I have rewound the spool with different line but it still reacts the same way.  What to do?
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Posted 4 years ago

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Kid Rock

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This could be a little bit difficult. Lightly tapping or slamming it are subjective terms. I can tell you from experience of having two different string trimmers. No make that three different string trimmers. The first was a corded electric model. The second was a gas string trimmer by a professional company. And the third is my current Ego trimmer.

On all 3 I would never consider extending the line to be the result of lightly tapping the head on the ground. It's fairly consistent between all three that it does require a bit of a bang in my opinion... Subjective opinion.

It usually works better to have the speed ramped up pretty high compared to some of the trimming that I do with it. And then if I don't "tap/bang" it hard enough it sometimes requires me to do it again. Until I have the speed high enough and until I tap it hard enough. The speed has to be high enough to produce the centripetal force required for the lightweight strings to pull enough when they are released to extend more line.

Maybe you know somebody else with a string trimmer and you can get their opinion. Or take it to the store and show a store employee and ask them their opinion. Have them check it out. Another possibility that wouldn't, probably wouldn't, cost too much... Is to take it to a repair shop and show them to see if they think it has a problem. They would probably be happy to check it with you as they want you to think good of them to forward their name on to other possible customers. What I'm saying his employees are usually pretty nice and helpful.

Short of posting a video hard for me to tell you whether or not I think you are having to type it too hard or not.
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Blue Angel, Champion

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I agree with KR.  The only time I have an issue with the 15" trimmer's bump feed is if I don't have it spinning fast enough when tapping.  I rarely need full throttle with this trimmer, but I'm in the habit now of ONLY using full throttle when bump feeding.

It also helps to tap on a solid surface rather than in the lawn if possible for two reasons... 1) the surrounding grass won't impede the line from pulling out as it spins, and 2) you won't shave a 15" brush cut circle into your lawn.  :-)

The only other thing that comes to mind is whether you might possibly have line binding in the spool?  If you still can't get it to feed properly at full speed, try taking the spool out and make sure the line is wound properly in the bobbin (all line in the bobbin and not caught between the bobbin and housing).  Caution: make sure to park the trimmer lines into the grooves in the top of the bobbin as you remove it, or the line will unravel and you'll be re-winding it!