Lubricating oil

[Surreypuma]

Hi, what would you guys use for lubricating oil for a Stirling engine? Have been using ptfe bike lube!

[Bumpkin]

Hi Surreypuma. I can't speak for one brand or type, but I think some of the bike chain lubes have a sticky formula to keep them from flinging off, and it might be too much friction in minimal power engines. The "dry" lubes might work well for bearings but maybe not for the seal for a displacer chamber or power piston. The other side of that "seal oil" point is temperature tolerance. Looking at the picture from your other post I would guess your engine has the transfer to the power cylinder from the displacer chamber hot end; workable but not usual, and something to consider in lubing the power cylinder if you run high temp. Shorter answer; most of these engines make such minimal power that you need to use the lightest minimal friction oil that you can.

Bumpkin