how petrol hedge trimmer clutch works?

[J.JJ]

can anybody explain how the clutch arrangement on a petrol driven hedge cutter
works or preferably can they direct me to a web site that shows a diagram of how it works and possibly shows how to adjust such a clutch. many thanks in advance john.

[thundercrack]

hi john, this won't be much help, but most are a centrifugal or fiction clutch, when you rev up over a certain speed the gubbins expands and grabs the drive plate. have had many of this type, strimmers , trimmers, chain saws etc. never seen one with any means of adjustment or instructions on how to. my last hedge trimmer I bought off of e-bay was a classic example. if you tightened the blades to cut better, then the clutch never kicked in until the engine was screaming. if you un-done the blades or oiled them too much, they would be operating most of the time, even at tick-over. very dangerous. I also found that a petrol driven trimmer got so hot it was a nightmare to use.
alf.