I have a 1991 red Homelite Super XL Automatic that oils just fine with the manual pump but seems to deliver little or no oil to the bar via the automatic oiler. I've pulled the plastic component that is next to the oil filler cap and checked the O-rings and the filter, all of which seem to be fine. I did not replace any of those parts. I'm not sure how the manual and automatic oilers share parts. I noticed that the manual oiler pump plunger has two grooves on the side where the pin that holds it in place can be engaged. Does it matter which of those two grooves I choose to insert the retaining pin into? Is there anything I should check or try before I replace the automatic oiler pump?