Thanks for that FoMoCo1. As far as I can make out, that is the most elaborate automatic chainsaw oiler I've ever seen. The piston (Item 10 of Figure 2) appears to be operated by crankcase pulsations. Overall, the manual and automatic pumps are combined into a single body, but operate by using separate moving parts. Items 2-9 are the manual pump, while items 10-16 are the automatic pump. I haven't found a way to adjust the amount of oil delivered by the pump, though.
