piston stop

[simonm]

1 of the screws that holds the metal casing around the flywheel on my stihl blower has come loose, I need to take the flywheel off to access the screw. Do I need a piston stop or can something else be used?

[spudulike]

You can use a piston stop or rope to lock the piston, you can use a flywheel wrench or possibly an air gun......personally, I would use a Stihl double ended plastic piston stop, unscrew the nut enough so it is proud of the crank and belt the nut with a hammer while holding the machine off the deck with the flywheel and with luck it will come off. If not, you will need a flywheel puller to pop it off but go easy, these ones are not that thick.

[simonm]

Are stihl piston stops universal? Out of curiosity how does the rope work?

[spudulike]

Are stihl piston stops universal? Out of curiosity how does the rope work?

 

The Stihl piston stop works on any engine with a 14mm spark plug hole.

 

The rope - use thick recoil starter rope, turn the engine in the direction of the nut or clutch to be taken off until the piston covers the exhaust port and then feed rope in to the plug hole until you can't feed more in and then turn the engine towards TDC and it will quickly lock and then the nut can be removed.

 

Some don't like this method as you can get rope stuck in the exhaust port or down the side of the piston or in the transfers but is reliable if done carefully knowing the pitfalls.