During the rebuild of my engine I couldn't find a good way to hold the waterpump shaft to under the impeller. There were also a few stress cracks in the plastic gear that are common. I tried using a screwdriver to jam the gear but wasn't happy that it wouldn't damage the teeth on the gear.

What I came up with is a socket that would fit over the gear engaging all the teeth. I made one on a 3D-printer, it has two tapped holes, the screws hold on a steel bar as a handle.

Worked perfectly

Hi there, welcome to the forum!

Nice idea for the tool. It took long time to design it?

I was using old t-shirt to hold the gear and used ratchet gun gently.

Good luck with rebuild