Has anyone have a brand new OEM stihl piston explode within seconds of the first start?

[HarleyT]

So the brand new OEM piston did not explode.

 

[HarleyT]

It was murdered.....

 

[Welder56]

Holy Harley give the guy a break. This should be a place we can all post without being flamed. Maybe all us normies can learn something

 

[GSully23]

After splitting the cases online thing I found was piston and rings.... nothing else was there that shouldnt be there, and with the small chance it lodged itself in the exhaust.....nothing was there either. That's why I was asking the question if it had ever happened before, since no ones has stepped in with a similar occurance I'll slap it back together with the meteaor piston and keep you posted. But no, there was nothing inside that shouldnt have been there.

 

[rich450es]

Was the arrow on the Piston facing the exhaust side or the intake side?

 

[Rick Stephens]

Sure looks like it hooked a ring at the top of the open transfer. Wonder if the rings were too big or out of round somehow. I now ALWAYS chamfer every edge, OEM or AM. It don't take very long and it *hopefully* prevents this. Doesn't look bad enough not to clean it up and put er back together, at least.

I put a saw together today that when I turned it over it before attaching muffler and carb it went 'scritch scritch'. It is disassembled on my bench again. Know the feeling. This was a ring rotated and sitting on a pin. I find it damn hard to know for sure I have rings aligned when I compress em.

 

[GSully23]

Harley can post all he wants...... he can troll me the same as I would if he stepped further into my field, but it's all good fun. Just because I dont have many post here doesnt mean I'm not as familiar with some things. I wish I had the time to troll others but I dont, so I just take it with a grain of salt and move on to the post that have meaning to them....

 

[HarleyT]

It hooked a ring?
Going up or down?

 

[HarleyT]

Nah, I am an equal oppurtunity arsehole....

 

[HarleyT]

Looking at the piston, and the port, what does it say?

 

[GSully23]

Arrow faced exhaust port.....

 

[HarleyT]

Looks like it hit something hard, to me.....

 

[HarleyT]

On the way up.

 

[GSully23]

Obviously on the way up, that's why the top has a smaller amount of damage and by the second ring it caused it to push down and out further due to obstruction.

 

[HarleyT]

So it hit something?

 

[HarleyT]

A pic of the top of the piston will show that?

 

[rich450es]

By any chance did you check squish when you rebuild it? If so what was the number you got?

 

[dmb2613]

Piston in backwards, or broke ring putting it together maybe ring not lined up with pin JMO

 

[dmb2613]

don't look like a new piston to me

 

[1Alpha1]

As others have stated, I'm going with the.......something metal hit something else that was metal.

Pistons just don't explode all by themselves.