Help! Stihl 025 chain won't stop spinning!

[Qdiddly]

Hello everyone,

New to the site but I'm having trouble with my stihl 025 that I just bought used.

The saw starts fine, but the chain won't stop spinning, even when idling. I thought it was a clutch problem so I replaced it with a brand new clutch, but it didn't fix anything...

Another thing is that the chain starts to rotate even when I pull the starter rope.

Any help would be appreciated!

Thanks

 

[HarleyT]

With the saw not running, and the bar/chain off, try and rotate the sprocket drum by hand. It should spin freely.

 

[Qdiddly]

When I do that, it doesn't spin freely, but I can spin it with some resistance

 

[HarleyT]

There will be a little resistance from the oil pump driver. But if the chain is turning when you pull the rope, something is binding/dragging.

 

[SEAM]

Is the worm gear lever engaged in the drum's recess? If not the gear might be slant and binding on the crank shaft...
Dirt between shaft and worm gear can have the same effect.

 

[Qdiddly]

The worm gear is engaged in the recess of the drum, but when it engages is when I feel drag when turning the drum.

 

[SEAM]

...in that case the worm gear does not turn freely on the shaft. Try removing the worm gear and clean/grease the mating surfaces.
There also is a washer (if I recall correctly) that, when installed in the wrong place, can cause the gear to bind against the clutch.
Chinese-made worm gears sometimes are too wide (and touch the clutch when installed) and may need some filing to get them to fit.

 

[Finnrpm]

Check that you have right clutch. Meaning that the round oiler protector plate fits between clutch and wormgear. Mine 023 has (old) original clutch and does not have this plate. If you install the plate it will lock the old model clutch and wormgear together, so it will be oiling all the time & spins the chain. In the end wormgears wirepin ( the thing that engages the wormgear to the clutch drum notch ) will give up and fails -> no oiling after this..... http://personal.inet.fi/cool/finnrpm/TI_42_2000_30_01.pdf
RV

 

[Qdiddly]

I took it apart again and found that there is no washer between the oiler worm gear and clutch... does that mean that my saw is missing the washer plate, or does it not come with one?

 

[HarleyT]

Here....

 

[Wood Doctor]

Take a look at this 025 IPL:

 

[Finnrpm]

I took it apart again and found that there is no washer between the oiler worm gear and clutch... does that mean that my saw is missing the washer plate, or does it not come with one?

You need to measure your clutch carrier, check posted T_I bulletin pdf-file. Check also the wormgear so it is not binding to clutch or anything else.
Old model clutch is without the protection plate/washer, new clutch ( OEM ) comes as a set, plate included. I have no experience of AM clutches for 025.
RV

 

[WRW]

I could be reading this all wrong, but my first thought is that the needle bearings in the clutch cover/sprocket are giving out.

 

[scottr]

I could be reading this all wrong, but my first thought is that the needle bearings in the clutch cover/sprocket are giving out.

I'm not a 025 guy but my first thought was a gummed up needle bearing or a rusted needle bearing .

 

[HarleyT]

I saw one once that had a thicker washer at the e-clip that caused the same trouble.