I have been rebuilding my MS200. I love this baby. Even it becomes a Frankenstein saw, where just about every single part has been swapped out, I want to keep it going. Most recently, I had replaced the cylinder and piston. They both came from the same seller. It was on Ebay. I have usually had good luck with OEM parts from sellers on Ebay. Well, after putting everything together, I fired it up. It sounded better than it has in a very long time, for about 15 seconds. The saw stopped, and I was not able to spin the flywheel anymore. After taking it apart again, this is what I found. The piston just crumbled. These parts looked great, and really looked like a match to the original piston and cylinder. Is this bad manufacturing? False advertising of parts that are not OEM? Did the piston rings spin after I compressed them to get them into the cylinder? I'm really shocked to see this and I wonder why this happened, and I am trying to figure this out before I put the old piston back in.
For background, I bought a new cylinder because the spark plug kept leaking during my pressure vac test. The threads were bad, so I redrilled the threads, and it kept leaking so I tapped out and got a new cylinder. A new piston came with the cylinder so I installed that just for the sake on consistency. No leakage during the last pressure vac test.