Chainsaw Repair

No, I mean a close up of the inside of the oil gear mainly, how it is different that the one on there now.

Sorry, the used parts went back to the owner with the saw. The difference in the oil drive gear is that the center of the old gear had two ears that fit into two recesses 90° opposed to the recesses for the old sprocket. The clutch drum did not have the elongated sprocket like the new one e.g. no star in the center.

If you enlarge the last photo in post #37 you can clearly see how the original drive gear slips over the clutch drum hub and is prevented from rotating by the engagement recesses for the sprocket.