Castrol Brayco 888 and 889

JohnSounddude

There was a previous discussion regarding Brayco 888. Unfortunately, someone posted erroneous information regarding that product. The poster (to my Knowledge) had no involvement or employ with Bray Oil nor Castrol. Statements were made that implied the product was intended for use as a Hydraulic fluid and may have been formulated with compounds similar to phosphate esters. This is totally false as are many of the other implications in that post regarding the fluid.

This fluid and its sister fluid Brayco 889 are fully synthetic, low viscosity synthetic hydrocarbons that are intended to be used as Heat Transfer Fluids. The 2 most common uses were / are in Solar heating systems and on-board electronics cooling systems in specialized aircraft applications. Bravco 888 nor 889 should not be used in any applications requiring Mil-Spec Hydraulic fluids or Hydraulic fluids formulated with anti-wear additives. Castrol / Brayco has other fluids for those applications.

In Solar heating systems, the current offering, Brayco 889 fluid routinely lasts 20 plus years in properly cleaned systems. It is true that Polyglycols have slightly better heat transfer capability, but they are NOT COMPATIBLE with Synthetic Hydrocarbons like Brayco 888 or 889. Yes, conversion from mineral oils, PAO's or SHC's to Polyglycols (PAG's) takes a lot of extra precautions and cleanings. But themz is the breaks.

EdTheHeaterMan

Thanks for sharing.

I wonder if you are referring to this post from 2003 https://forum.heatinghelp.com/discussion/comment/775975