[scrappleby]

any idea what could be happening here? thing vibrates so bad can't hardly hold onto the damn thing. right now it has a bump to advance string spool. stihl brand. I've noticed the handlebar and driveshaft tube is loose where tube secures into motor housing. I've tightened everything but it's constantly loose. is there something that usually goes bad here?

 

[Scott87]

sounds wore out. I don't think they've made a FS85 for 25 years. My guess is for the crankshaft is failing.

 

[scrappleby]

ohhkay that's what I wasn't hoping to hear. thank you tho

 

[Toro44]

The crankshaft is failing? It’s probably in the driveshaft or the clutch. There’s 2 t27 screws holding the trimmer head on. Take the trimmer head off and pull put the inner shaft. Then run it and see if the vibration goes away. If it doesn’t it’s in the power head.

 

[dieselss]

I'd actually pull the trimmer head off first(easier) then try it.

 

[Breezmeister]

Number 16 is the clutch drum, it mounts in to number 13, the fan case. The bearings in the fan case could be shot or were the bearing mount could be worn out. Number 18 is a rubber damper,that could be worn out too.
You need to take the drive shaft out and look at the end of it, if it's tapered, (not flat/squared) then the shaft needs to be replace with the clutch drum and what ever is worn out, bearings, fan case, rubber damper....And the clutch if there is a broken spring or if it's worn out.....
That's if you can get the parts......
.

 

[DA Quality Lawn & YS]

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