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Got some used oem pistons to practice on and decided to cut one in half. I did not expect to see an insert of some kind for the top ring grove. It doesn't stick to a magnet, but it is definitely harder than aluminum.
I made the cut off-center and this is the short side. I'm thinking a corner rounding bit to take down the top edge should be good. I haven't taken any measurements yet, but the top radius of the lip is the only thing I see that could be called "sharp".
7 more to figure it out.
The lip looks quite thick with a generous radius on the edges. Further reinforces my theory that the talk about them being stress risers, and therefore requiring removal, is misguided.
What would really be interesting is sectioning cracked pistons. In the early stages before failure to give a look at the origin.
I got these pistons for free, with unknown mileage and history. I was hoping there would be some cracks but none of them appear to have any. They are crusty though, with a lot of buildup in the rings.
Got some used oem pistons to practice on and decided to cut one in half. I did not expect to see an insert of some kind for the top ring grove. It doesn't stick to a magnet, but it is definitely harder than aluminum.
I made the cut off-center and this is the short side. I'm thinking a corner rounding bit to take down the top edge should be good. I haven't taken any measurements yet, but the top radius of the lip is the only thing I see that could be called "sharp".
7 more to figure it out.
I've never seen a diesel piston that didn't have that "steel" ring land. Surprised that it isn't magnetic. I always assumed they were just carbon steel or something like that.
What would really be interesting is sectioning cracked pistons. In the early stages before failure to give a look at the origin.
I got these pistons for free, with unknown mileage and history. I was hoping there would be some cracks but none of them appear to have any. They are crusty though, with a lot of buildup in the rings.
I'm in the middle of rebuilding my 7.3. I have 3 pistons that have cracks in the lip of the fuel bowl that didn't completely fail yet.
The lip looks quite thick with a generous radius on the edges. Further reinforces my theory that the talk about them being stress risers, and therefore requiring removal, is misguided.
Old post but...
Your theory is 100% incorrect.
Nearly every motor I have lost in the last 25 years has been due to cracked pistons. And guess where those cracks start...
