Hi folks,
I'm in the process of putting together a small horizontal I/C engine (in the style of the Kerzel HHM1 / Farm Boy / Odds 'n' Ends designs).
Most of these have a drip feed oiler on the cylinder liner to lubricate the bore and (in some cases at least) the small end.
My question is whether the feed port from the oiler needs to be covered by the piston skirt at all times, or if it is acceptable for the skirt to uncover the port as the piston approaches TDC?
My concern is that a very long piston skirt would be needed to keep the oil hole covered, but if the port is uncovered, doesn't it make it likely that the oil will be drawn into the bore as the piston ascends, then flung out of the bottom again as it descends (without getting anywhere useful)?
(I'm taking it as read that the port will be positioned below any part of the bore traversed by the piston ring.)
I've looked at the Webster plans, and it seems that the oil port does get uncovered, but in a number of videos of people running them, there does seem to be a lot of oil spat out of the bore.
Any hints or tips appreciated…
(Engine is 20mm bore, 26mm stroke, cast iron piston in a steel liner. Phosphor bronze connecting rod bushes).
Thanks in advance,
Andy
Edit to add: There doesn't seem to be much IC engine activity here – would I be better off asking on another forum?
Edited By Andy Gray 3 on 11/09/2020 23:09:37