Maytag A712 : Large mixed load 9 minute wash.

This is my newly acquired 1983 Maytag A712. This machine needed nothing when I got it and seems to run well. The tub is yellowed and I'm not too sure why that is or how to get rid of it. Overall I am very happy with this machine and I expect to use it for the foreseeable future. Please pardon the shaky final spin, I live in a mobile home that does not have the most solid floors. I am sure this would shake less if on a more solid floor. Cycle : Regular 9 minute wash Temp : Warm/Cold Speed : Fast/Fast Load size : Extra Large Detergent : Tide Free and Sensitive