USE ONLY GENUINE ROCKER BOX LUBE
Here is the how and why of the fine old art of rocker box lubrication in clear detail.
This lovely excerpt is from the Pratt & Whiney Wasp Junior flying manual.
Anyone flying a greaser should read these pages with the pleasure and patience of a nice cup of coffee.
We hope your A&P IA will enjoy this, and appreciate too that to pilot a greaser is delicate art.
We recommend the following intervals for open-style rocker boxes (e.g. LeBlond, Lambert, Ken-Royce, Liberty):
Valve guides, springs, tip rollers: 2.5 to 3.5 hours.
Rocker bearings (the zerks) 5 to 7 hours.
Pushrods not to exceed 15 hours.
For closed boxes (such as Kinner, Pratt, Wright and Warner):
lube exhaust guides at 5 to 7, inlets not to exceed 15,
and otherwise adhere to the open box intervals.
As the manual says (more or less), engines lubed frequently with love and care will work better and last longer.