Got the new (used) gas engine in the 3400 today. Since I had to swap the oil pan and the head, I figured I might as well pull the pistons and check it out. The previous owner said it ran when he took it out to replace it with a diesel, but said it used oil. I think I figured out why... As you can see, the top ring on the front piston is broke into multiple pieces. But I also noticed the top edge of that piston has a few chips in it. I checked he cylinder and it has a spot in the top edge in the same spot as the piston chip. Its not deep, but definitely worn in that spot. I planned to hone and re-ring the cylinders and pistons. I can replace the rings, but I'm wondering if that spot in the cylinder will just cause problems with the new rings. Is the piston OK to use? Do I need to replace the sleeve in the cylinder? Thanks
Oh and in case you are wondering, the line you see in the bottom half of the piston is not a crack.
Oh and in case you are wondering, the line you see in the bottom half of the piston is not a crack.