Vintage Windmill and Wind Generator Forum

McMaster-Carr (mcmaster.com/non-detergent-oil) carries a wide variety of non-detergent lubricants, including 10wt, 5wt (ISO 22), and lighter. 5wt. oil is also available as motorcycle fork oil. The original Aermotor documents say to use an oil that is "less than 10wt". Other people here probably have ...

Maybe this has already been resolved, but have you tried disconnecting the pump rod and running the mill without the pump? If the noise doesn't go away you could probably rule out a problem with interference in the pump stroke. However, it's also possible that the "no load" condition might give an ...

O'Reilly Auto Parts (oreillyauto.com) carries two types of 10 wt. non-detergent oil at reasonable prices. One type has rust and corrosion inhibitors but no detergents. The other type has no additives whatsoever and costs a little less.

Brock's Performance (brocksperformance.com) has "Less than 0W ...