Husqvarna 357 Mystery

[cdntbone303]

Bought a blown up 357xp. Looked like crank bearing went when I bought it based off of looking at top of piston. Got new bearings on way home. Got it home took seals off to inspect bearings and all is good , what the hey! Bearings good, no slack, rotate freely except some loose metal or something at bottom of case the crank catches on. Cylinder walls are nice with slight transfer and a banged up roof and a broken muffler bolt hole. I looked everything over to find out where the metal came from(Bearings/cages/stuffers/crank and couldn’t find anything. I do not recall the ring being damaged when I pulled it off either. Maybe muffler gasket? It was in pieces in a bag that came with the saw. Any ideas when caused this ? I included a few good pictures. It’s an early model with 13mm piston rod end. It’s narrower on top then bottom, that normal?

 

[Yukon Stihl]

Got one like that where the big end of the rod bearing let loose

 

[cdntbone303]

Got one like that where the big end of the rod bearing let loose

I looked at the bearing and rotated it in the lower part of crank rod and look intact. Piston pin bearing too intact

 

[HiOctane]

From what i understand,you didnt split the case.Split the case,remove crank bearings and check cage condition ,same for big end,cage could be broken or needle loose inside the cage itself.Have a look also if bolt holding throttle,choke flap is not missing.

 

[Cantdog]

Is the ring end locating pin still in the piston groove?

 

[pioneerguy600]

There is bits of what caused the damage still embedded in the piston crown.

 

[cdntbone303]

Is the ring end locating pin still in the piston groove?

Yes

 

[cdntbone303]

I looked over the piston and compared it to another that blew a bearing cage on the clutch side. No scoring on sides of piston from metal coming up from below compared to other one with blown bearing except some melting which is stuck to wall of cylinder. Pictured is piston of this saw

 

[cdntbone303]

Here is a piston from another 357 that blew clutch side crank bearing. Notice the scoring/gouges in the sides where the metal came up through especially in pics 1/2/4

 

[GA_Boy]

Maybe it ate a spark plug anode/ground.

 

[cdntbone303]

Maybe it ate a spark plug anode/ground.

Maybe there was a sparkplug in a bag with other parts from the saw, but is was all intact. Whatever happened here I believe it came from above and not from below in the crank area

 

[GA_Boy]

Maybe there was a sparkplug in a bag with other parts from the saw, but is was all intact. Whatever happened here I believe it came from above and not from below in the crank area

Plug could've been changed out and kept running it, couldn't have gone that many rev's with no spark

 

[Old2stroke]

Any chance it ingested something through the carb? Was the air filter on it?

 

[cdntbone303]

Any chance it ingested something through the carb? Was the air filter on it?

Not through the carburetor. I checked the bellows and all is intact there

 

[cdntbone303]

Plug could've been changed out and kept running it, couldn't have gone that many rev's with no spark

Might be onto something here though all those notches in the top of the piston look like about the size of a spark plug ground. Larger/deeper then that of bearing cage notches in the top of my other scrap piston