Horizontal engine cylinder lubricator

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

All the open crank engines I have made the oil hole is uncovered often for at least 50% of the time so no problem having it in the usual place at the crank end of the cylinder.

Somewhere like MEM forum has a more engine focused membership and with a good proportion of members from the US then open crank hit & miss style engines are more common as well as the usual IC subjects..

Brilliant - thanks very much.

I can drill the hole in the liner now and get on with putting it together!