Anyone with knowledge on strimmer engines?

[spikeyhead]

or a blocked air filter

[coaster2coast]

Might have the solution for you, a lot of strimmers have a small mesh on the exhaust take it off and see if it needs cleaning (i just leave it off) i have a Spear and Jackson 48 and this was the problem. Happy revving!

[Jamiemilliken]

I hope I am in the right place to ask this question, I am a newbie, my question is about a Petrol strimmer. It’s starts fine the problem I am having is when it is running the engine revs up and down and is not consistent can anyone please help to shed some light on to possible causes please