Starter drive issue

[Pepsi Mechanic]

I need some advice re a starter drive problem on our Early 1928 AA Pepsi truck . I recently had my old starter drive ( 1/2 shaft ) break . I have a spare starter on my shelf with a 5/8 shaft and drive . I installed the spare and when I went to start the truck the drive was very noisy engaging . The engine would turn over and start . Is this normal ? I managed to get the drive parts for the original 1/2 inch ( 1927 model T part ) and rebuilt and installed . It is much quieter . I also noticed that the ring gear was slightly damaged as well by the 5/8 in starter . I managed to file it clean
Why does the 5/8 in. not work right ?