Fs250 bad clutch?

[jacrawley]

I have an still fs250 that runs but the trimmer head does not spin. Sometimes when it is off spinning the trimmer turns the piston over other times it moves freely. Is this a bad clutch? Are there other things I should do to diagnose?


Update. I have removed the engine and the clutch bell spins freely but this does not turn the trimmer head.

2nd update. The drive shaft is sliding back towards the engine causing gear box at the end to disengage. This is a friend's and has been sitting for a long time. Perhaps someone else removed a component from the clutch end that prevents the shaft from moving in that direction?
Thanks

 

[Ax-man]

I'll take a stab at this only because I have worked on a few of these at my little part time job and kind of ran into the same problem . The clutch itself was rusted solid on the one I worked on with the same problem.

Do a process of elimination . First remove the shaft from the power head. Make a mark on the outer tube so you can see where your at. You should be able to turn the gearbox with your fingers if the drive shaft is seated correctly in the gear box. If you can't do this then you have a problem either with the gear box or the driveshaft itself is stripped out providing it is seated in the gearhead. It doesn't take much for that driveshaft to seat into the gearbox . If that checks out then the problem is with the drive sprocket or the clutch. The driveshaft must also seat into the drive sprocket or otherwise it won't turn the gearhead. If this checks out then you have to go after the clutch by removing the drive sprocket to inspect the clutch. If you a have to remove the clutch it is a right hand thread , just the opposite of a chainsaw. That clutch is also different than a chainsaw so make sure you get it back together correctly if you need to take it apart. How to take it apart and put it back together is beyond the scope of discussion on a forum like this .

My money is on the clutch . The other components in the drive train are made of some pretty stout stuff because of the abuse these tools see mostly cutting brush they shouldn't be cutting. Anything can break from the gearbox, a rounded out drive shaft or drive sprocket or even a broken drive shaft. It can also be just a minor problem of the shaft pulling out and away from the powerhead just enough that it won't turn the gearbox which is why you should mark that outer tube when taking it apart.

 

[jacrawley]

Turns out the shaft was not inserted all the way into the motor which gave it enough room for the drive shaft to move back and forth and disengage. Now that's fixed but the clutch does not disengage when idling.

 

[Ax-man]

Yep , that shaft not being inserted all the way is a common problem on those trimmers and really annoying on those power pruners. Looks like you have to get it that clutch . It could be as simple as too much debris packed around the shoes . It has been awhile since I did that one clutch but clean that clutch up good on a wire wheel to see any markings before taking it apart . It has to go together the same way it came apart or otherwise it won't mate right with the drive sprocket that turns the shaft . I don't know if that clutch is sold as a complete assembly or not . All I remember is I had to knock out those pins which was a pain in the rear and replace the shoes . It is not a hard job just different . I am probably making a big deal out of this but I am sure you can handle it if you have gotten this far with it.

 

[jacrawley]

Clutch was rusted up from sitting to long. Bought a complete new clutch and fixed it up.

Thanks