Jewell is non-pouring oil for manually greased valve trains, usually called "grease"
Jewell Amber Oil -- formulated for vintage engines
We are proud to have re-introduced purpose-made rocker box grease to the market in 2005. The reason was simple: the makers of the most reliable greasers ever built, the Pratt & Whitney and the Wright, were very clear: NEVER USE A YELLOW GREASE, one with fillers, use ONLY A NON-FLUID OIL!! Warners and Kinners are no different. The valve springs in LeBlond, Lambert, and Rearwin's Ken-Royce derive additional benefit.
No other such lubricant is still available. Gone for half a century now are all the standbys we depended on: Esso's No-Ox-Id-E, Marathon Rocker Arm Grease, Richlube's 'High Pressure' and 'Combat' Rocker Arm, Penn Gear Medium and Heavy, aviators' favorite Mobileoil Gargoyl C, Pure Oil Aircraft Rocker Arm Grease, Phillips and Shell 'Rocker Arm', and Standard Oil of California's famous all-season Rocker Box Grease.
Substitutes and airfield experiments now abound. Aahh ... dirt strip legend. Good old Texaco Marfak (also available from us) was the choice of some manufacturers even back in the day, such as Kinner and Warner. That and other low-melt bearing greases have become the default for valves. But they're easily displaced, they also tend to cake. Supposedly they melt. But contrary to popular fiction, for example, low-tech Marfak itself does not melt at temperature, it just separates. It becomes a teeny quantity of worthless oil of perhaps w5 ... and globs of solids. Worse still, and importantly, it does not become homologous again on cooling. Never. Just what P&W wanted to avoid. Try it yourself: heat some on a screwdriver one day and watch ...
They are NOT rocker arm grease -- they are hub bearing grease! And that's why we make the best -- the ONLY GENUINE AIRCRAFT VALVE GREASE on the market. You will see the difference (on your windscreen too) after your first flight. And the gurus of small radials will still have plenty of work, not to worry: they don't need you using Marfak to keep them in business (even though it helps).