mcm vintage KitchenAid KD-20 Dishwasher - $199 (Richmond)

This is a vintage KitchenAid Energy Saver V Superba by Hobart dishwasher original to our home which was built in 1961.
It will run on only certain cycles, but I can’t seem to get it to run on heavy wash or any of the other main wash cycles.
The pump is clean and the drain valve is good- I was told to look into replacing just the mechanical timer and that should fix it.
I purchased the 40 page service manual online, but honestly just have not had time to try that hard and have resorted to selling! There is a small rust spot inside that could be cleaned, otherwise all of the parts and interior/exterior are in perfect condition.
If someone is a little handy or knows somebody who is, I think this could probably be a fairly straightforward fix! Serious inquiries only- cash or venmo only.