Pictures of ms 362 cylinder/piston failure

[D B Cooper]

Ok I have never seen a failure like this one before.

On with the carnage!




I see where the plating has been worn off the bore at TDC / BDC .

 

[GlocknStihl]

Is that the first edition cylinder or the revised cylinder?

 

[Stevetheboatguy]

Not positive, but the cylinders that I have seen worn like that are usually on newer strato saws. I'm going to guess it's due to the piston balance and the way it rides in the bore. They generally have a longer skirt on the intake side and seems to create more wear than what we are used to.

The piston looks like it ate the locating pin? Is that correct? That's usually due to fatigue or heat in my experience.

Steven

 

[Fruecrue]

Weren’t some huskies doing something similar? Maybe 562s? I believe they determined ring flutter was root cause to the pins coming loose.

 

[Marshy]

Ring flutter comes from over revving from my understanding.

 

[D B Cooper]

The locating pin is still in there, it is worn away.
original cylinder, saw d.o.m. is 6/14.
I notice the ring with the flat edge was broken off. Wonder if it got a chunk broken off at assembly and rattled around in the groove till failure?

 

[huskihl]

Left ring pin broke off and the ring end moved over and caught in the transfer port

 

[Chainsaw Jim]

Ring flutter comes from over revving from my understanding.

I read that it's from trapped gas between the rings interfering with the ring tension against the cylinder wall. It says the remedy is to take the lower ring and increase the gap enough to vent a little bit.

 

[Bigmac]

On a cr250 but still, the ring looks like it’s missing but..
But it’s still there!?!?
Cylinder destroyed

 

[AlfA01]

Left ring pin broke off and the ring end moved over and caught in the transfer port

Yep. It looks like it beat around in there for a while before it finally hung the transfer port.

I read that it's from trapped gas between the rings interfering with the ring tension against the cylinder wall. It says the remedy is to take the lower ring and increase the gap enough to vent a little bit.

I've also read that some of the 560/562 piston ring pins become loose and recess into the piston. They allow oil and gasses to pass behind the ring which gives a false high compression readings. Whether it's gas or fluid, I can only imagine that would cause a hydraulic effect with the rings also.

 

[D B Cooper]

Found the updated cylinder and piston from a type 2 installed caber rings. used the new carb box and version 3 m-tron carb and coil. don't like the new 10mm sparky plug,another i have to keep in the spares kit. Tuning with the new version 3 is easy. got 4 tanks thru it so far it keeps getting stronger.

 

[AlfA01]

Cool. Nice username by the way. Did they ever catch that guy?

 

[TreeLife]

Cool. Nice username by the way. Did they ever catch that guy?

Yeah DB...wheres the money? Lol