Has my Stihl BG86 Seized? (Please watch attached video :))

[MattyF]

I've had con rod disintegrate on one as well.

[spudulike]

I've had con rod disintegrate on one as well.

 

Now that doesn't surprise me Matty:001_rolleyes:

[Darkslider]

Spudulike, you're a winner! One of the flywheel housing bolts had unscrewed enough to jam the flywheel just as you and the others said. Removed them all and threadlocked them back in and it's running fine now. We were quite lucky it was only running on idle when it jammed, so cut out and wouldn't turn over when attempted to re start. If the bolt had jammed at full revs it might've been a different story!

 

I've still got the old one that suffered a shattered big end bearing and broken piston rings so had a look at that, but no signs of any impact damage/scoring on the flywheel of that one so must've been something else that caused it.

[spudulike]

Spudulike, you're a winner! One of the flywheel housing bolts had unscrewed enough to jam the flywheel just as you and the others said. Removed them all and threadlocked them back in and it's running fine now. We were quite lucky it was only running on idle when it jammed, so cut out and wouldn't turn over when attempted to re start. If the bolt had jammed at full revs it might've been a different story!

 

I've still got the old one that suffered a shattered big end bearing and broken piston rings so had a look at that, but no signs of any impact damage/scoring on the flywheel of that one so must've been something else that caused it.

 

 

Got to say it was Barrie (Gardenkit) who said it first, I was just agreeing.......robustly:lol:

 

Glad we were right:thumbup:

[GardenKit]

Got to say it was Barrie (Gardenkit) who said it first, I was just agreeing.......robustly:lol:

 

Glad we were right:thumbup:

Haha, only because I read it first Steve:big grin:

 

Glad you got it sorted Darkslider, shame you pulled it all apart first though!

[Badger Bill]

Hi, I had the same problem, but it's also sheared the woodruff key on the flywheel, does anyone know if the key is replaceable,or is it a new flywheel.

thanks

Bill

[Michael Mcallister]

Had the same problem and I know nothing about engines. Just took it to pieces put it back together and is working fine. Could have been what the others are saying about a loose bolt.

[lurkalot]

On ‎20‎/‎11‎/‎2014 at 19:17, GardenKit said:

A very common fault on these machines is that one of the 3 torx screws which hold the magneto mounting plate to the crankcase comes loose and unscrews until it locks the flywheel.

Yep they seem to have a big problem with those screws coming loose, and like you I've seen it many times.  Also had the screws on the other end inside the fan housing come loose as well, though it's not as common.