Jewell is non-pouring oil for manually greased valve trains, usually called "grease"
Jewell Amber Oil -- Rocker arm grease for vintage engines
We provide the ONLY purpose-made rocker box grease on the market since '05. The reason is 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 volute valve springs in LeBlond, Lambert, and Rearwin's Ken-Royce derive further additional benefit. Without our product folks would have to use wheel bearing grease in their airplanes' engines! Lindberg would have cringed.
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, but is no longer formulated as it was in the pre-war years, Makers such as Kinner and Warner did not intend for you to use a #2 bearing grease in their engines' valve train -- NEVER!!!
Unfortunately, however, Marfak and
other low-melt bearing greases have become the default for
valves: 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 operating temperature: it just
separates. It becomes a teeny quantity of worthless oil (of perhaps w5)
... and globs of equally worthless solids (soaps and fillers). 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 ...