kirbvacsrock
Walker,
Yes, of course there were.
Units built prior to serial #F500000 not only came with metal fans, but also these had the speed switch mounted to the inside of the headlight cap, also with a lock, to ensure the machine would not run unless any of the front-mounted accessories (rug nozzle, hose, Crystalator, Miracle Head, Handi-Butler or Rug Renovator) were properly attached.
This speed switch was notorious for being busted as some users would slam the headlight down toward any of these accessories, which had a metal pin that jibed with one of two slots on the speed switch (one for low speed, one for high speed). Kirby issued an advisory to its service centers in early 1980 to bring in any of the affected units for conversion to the bottom-mounted speed switch (as last used on the Classic III) free of charge.
At first, when Kirby changed back to the speed switch as mounted on the fan case below the intake opening, a blue dust cover was installed around it, to keep moisture out of the switch when the Rug Renovator was being used. However, that was still problematic as the speed switch arm ended up getting jammed, causing the motor to run high all the time. Thus, Kirby then advised its dealers to remove these covers.
Apparently, the one that you have probably had its metal fan replaced a long time ago. Your example falls between serial no. F500000 and F999999.
~Ben