The centrifugal clutch in a chain saw is connected to the crankshaft and uses counterweights and friction pads to keep the engine idling at a low RPM. Understand how a centrifugal clutch works in a gas operated chain saw with instructions from an experienced carpenter and construction specialist in this free video on power tools.
Hello, my name is Mark Blocker, in this segment we're going to cover how the centrifugal clutch on a chainsaw operates. OK what I have here is a chainsaw, gas operated chainsaw, I've removed the bar and the chain and the cover that holds the assembly together so we can have access to the centrifugal clutch. And how the centrifugal clutch operates is this outside portion of the clutch free spins, that's the sprocket that drives the chain itself that does the cutting. The inside portion is connected to the crankshaft and as the name implies it operates centrifugally. It uses spring around here, two counterweights which are connected to two clutch discs or friction pads. The spring holds the two counterweights in while the engine's idling at low RPM as the RPM increases, the counterweights centrifugal force exceeds the spring pressure and starts sliding, well let me see if I can get this here, I'll just do one at a time, and that slides outwards see how it applies that friction disc to the outer housing which connects and drives the sprocket that drives the chain on the bar. That's how the centrifugal clutch operates on a chainsaw.