On 01/26/2020 12:51 PM, newshound wrote:
I have a 12 year old Ryobi RCS4450C which has stopped feeding chain oil. It looks to me as though there might be some sort of pump on the crankshaft behind the drive sprocket and the centrifugal clutch (I only have a low-res exploded diagram, with parts labelled but no "key"). Before I do any more dismantling (it took a while to get this far) can anyone confirm I am likely to be right? I'm assuming that most petrol chainsaws have similar layouts.

TIA
I had some luck with image searches for 'chainsaw type Parts List'.
(yes, on the one here, the pump is behind the clutch, near the drive gear, but finding all the screws you'd have to loosen is a matter of luck without a proper diagram)