Stihl FS400 HEad keeps spinning

[Rich2484]

Sorry typo. The clutch boss not carb. Obviously nothing to do with carb

 

It's the space between the clutch "outer parts" that give away if any of the springs are gone. The gaps will be different. It's one tell tale sign, its not always that easy to spot. But one thing to look for.

 

It's also easier and better to just change them anyway.

 

And not your clutch but what one looks like. Thought I would throw a pic out there.

[champagnecharly]

Ok.. So by broken springs its not broken as in 2 or more parts but that they have lost their memory and dont return to where they should?

[Rich2484]

Ok.. So by broken springs its not broken as in 2 or more parts but that they have lost their memory and dont return to where they should?

 

Spot on. Ish

 

But they can also break. Many a time have I and probably others have removed a clutch and a spring is in two pieces.

 

But normally the machine in question has been run on and the broken part of the spring has made its was behind the clutch and taken Grand Canyon gouges out of the casing behind.

[champagnecharly]

the internals all look good. is it wise to just change the springs and give the rest a good scrub and soak in wd40? 50p each compared to £20..

[Rich2484]

Yeah can do. Most of the time the clutch parts are ok. I have only ever replaced one whole clutch because it was gone.

 

Some wd and a wire brush is good. Just be carefull of the outer edge that is the touching edge of the clutch parts that makes contact with the drum. A bit of fine emery on it and don't go mad.

 

For 50p a spring can't go wrong.

[GardenKit]

If the engine tickover is as low as it will go, the problem lies with the clutch. If the springs are weak, or broken, as said, then the shoes will fly out to easily.

 

Alternatively, one or both shoes could be stuck out and not returning. These clutches are prone to siezing on the shoe pivot bolt and bush, or between the guide plates, usually due to rust after a period of storage. Take it apart and give it a good clean up, or replace the whole clutch.

[champagnecharly]

Thanks guys.. I'll try the springs and wd40 and see what comes of that.

[lakeyboy]

Just out of interest is the idle speed controlled by a little slider in the handle the throttle is on ? Sure i have seen it an ipl for a long reach hedge cutter

hope you find a solution

Tim

[champagnecharly]

Hi,

 

No its the standard cow horn with trigger & release.

 

Regards