Manual oil pump question on my 3400, when first mashing pump level has good resistance, after that its real easy, let sit 15 to 20 seconds and firm again on first push then easy again. Does that sounds like it time to replace the pump plunger seals, oil does flow good on first push then not much after that.
Steve
Could be worn, but not likely as that's a 2 sided "quad" O-ring and by design it seals both ways. I assume that the auto-oiler is working OK..
Refill rate into the pump body is dependant on 6 different items; oil thickness/temperature, pick-up screen, hose pinholes/kinks, inlet and outlet check balls & springs in the pump body, and then the tank vent/cotter.
I just had to order a used pump body from Acornhill last month because the intake check valve was stopped up by fines & couldn't even be cleared with carb cleaner, 100# shop air & a small wire. It picks up & oils great now.
Are you running the "Summer" thick oil?
Have you pulled the pump assembly out to inspect & pressure test the two midget sized internal checks?