Yep, My 70 year old SU H2 Carburetors have an oil reservoir (complete with their own little dipstick of a sort) which need a few oz of oil in each.
Original Manufacturer SPEC is straight-20 weight, which a lot of people claim is important to ensure the proper viscosity for piston operation under normal operating temperatures. The way it works is kind of like a shock absorber, where the oil bath creates a film to both lubricate, and to slow down the motion of a spring loaded piston, which is pulled up by the engine vacuum. The way this is set up, is so the piston is normally down, and has a slight upward force from the spring, and as the engine's demand for air increases, the piston rises in order to permit more airflow, thus automatically adjusting the Fuel/Air mixture
Anyway, long story short, I need a yellow-metals safe oil roughly equivalent to SAE20w or equivalent viscosity to SAE20w at as wide of a temperature range as I can get (20w20?) Which is yellow-metals safe... This is not a high speed or high wear item, so additives or a lack thereof are probably un-needed.
Ideas?
Original Manufacturer SPEC is straight-20 weight, which a lot of people claim is important to ensure the proper viscosity for piston operation under normal operating temperatures. The way it works is kind of like a shock absorber, where the oil bath creates a film to both lubricate, and to slow down the motion of a spring loaded piston, which is pulled up by the engine vacuum. The way this is set up, is so the piston is normally down, and has a slight upward force from the spring, and as the engine's demand for air increases, the piston rises in order to permit more airflow, thus automatically adjusting the Fuel/Air mixture
Anyway, long story short, I need a yellow-metals safe oil roughly equivalent to SAE20w or equivalent viscosity to SAE20w at as wide of a temperature range as I can get (20w20?) Which is yellow-metals safe... This is not a high speed or high wear item, so additives or a lack thereof are probably un-needed.
Ideas?