ROTTLER HM3 HONE REPAIR
Here is how you can repair the Hone head since Rottler does not service the head any longer. You can use a Regis part number RSI218. You will need to drill out the top of pinion to remove the expander nut. Then cut the top of the shaft and drill and tap it for a small bolt. Then put on the bolt and washer and you are ready to go.

Charlie Corria
Charlies High Performance Machine
Tracy, CA
August, 2017