Husky 440 twisted bent crank maybe

[Old2stroke]

Hard to twist a crank, they're built to stand the force of sudden stop when the brake is deployed at full rpm. If there is any significant twist, it means the two ends are no longer on the same center lines but when it's installed in the crankcase the two ends are forced to turn on the same center line and this produces wobble stress of the case bearings and radial run out of the two ends along with end plane wobble of both ends.. Not good.

 

[SteveSr]

How is this saw constructed, plastic / metal crankcase? I am wondering if the sudden stop fractured / distorted / broke the crankcase leading to a variable FW - coil gap which caused the timing changes.

 

[farmhard]

Hard to twist a crank,

I would agree. On the saws I get they have ingested cement and you don't notice it with bearing wobble until you press back together which can be tough if you didn't quote for a crank and customer "decides" you bent it.
I just redid a easy start BR recoil where the crank seemed fine by hand but destroyed my new recoil from too much drag.

 

[farmhard]

How is this saw constructed, plastic / metal

It's a Poulvarna.
My guess would be he checked the flywheel and either had oil on the crank or didn't torque it properly. There was no reason to suspect the crank as bent, but IMO if you rule out the piston ring and jug I would change the coil over playing with timing. If I did that on a customer saw it comes back and I work for free when the coil does pack it in. If the key was sheared there sometimes is an indication of loose nut or bright metal where it turned.
We all learn somewhere, somehow sometime and most respect to those who try.

 

[Chevboy0167]

Plastic crankcase for those playing along at home....

 

[Bob Hedgecutter]

Plastic crankcase for those playing along at home....


View attachment 1230568

Past playing- too many anomalies, too little photographic evidence- not quite sure what the entire post is about.
Almost- okay, its gotten the better of me- cant quite put my finger on it- Ive decided the crank must be bent, therefore there is no other answer.
Key and keyway are fine- but the timing can be manually retarded and advanced....... until a miracle flywheel position is found and the saw runs- but the bottom end is trashed.
Im out.

 

[pioneerguy600]

Past playing- too many anomalies, too little photographic evidence- not quite sure what the entire post is about.
Almost- okay, its gotten the better of me- cant quite put my finger on it- Ive decided the crank must be bent, therefore there is no other answer.
Key and keyway are fine- but the timing can be manually retarded and advanced....... until a miracle flywheel position is found and the saw runs- but the bottom end is trashed.
Im out.

I was out at the first mention it was a Husqvarna 440 , there is 4 of them sitting here in the junk pile as that is were they belong once badly damaged. All of the ones here were straight gassed by the homeowner class of saw owners that buy these cheap disposables. Not worth putting a new P&C in them, if they get a bit hot from the dull chain gang running them hard the bearing pockets let go.

 

[farmhard]

Bob,
It's AI having a go at you. Next week will be the Tik Toc shorts on how to pet a chain at full throttle and how to unfell a tree.