1957 62 Series Brake Booster Lubrication

[DaveW]

I recently purchased a rebuilt brake booster for my 1957 62 Series car.  This unit mounts on the dash and is sometimes referred to as the Hydro Boost unit.  There is a threaded plug on the back of the unit that the shop manual refers to as a lubrication plug.  I can find no reference in the manual describing the type or amount of lubricant to add to the unit at this location.  Would I simply use brake fluid?  If so, how much?  Fill to the bottom of the threaded hole?  Can anyone provide the correct information?

[Mike Josephic CLC #3877]

I recently purchased a rebuilt brake booster for my 1957 62 Series car.  This unit mounts on the dash and is sometimes referred to as the Hydro Boost unit.  There is a threaded plug on the back of the unit that the shop manual refers to as a lubrication plug.  I can find no reference in the manual describing the type or amount of lubricant to add to the unit at this location.  Would I simply use brake fluid?  If so, how much?  Fill to the bottom of the threaded hole?  Can anyone provide the correct information?

DAve:

Not 100% sure about you '57 -- but the older units (Bendix Hydrovac, etc.) had
leather parts in the works that required a special oil to keep them supple.  The
replacement is "neatsfoot oil" which is a leather preservation compound that keeps
the pieces supple and pliaible for use.  You can purchase this at any hardware
store.  Don't use brake fluid.

Check your shop manual.  Mine states that the pipe plug on the unit was to be
removed and every 2,000 miles checked and fluid added to bring it up to the
level of the plug.  The fluid specified was "Delco Hydraulic Shock Fluid", which
is no longer available.

Mike 

[DaveW]

Thanks to Mike and others who have replied with help.  It is much appreciated.  Seems to be unanimous that I should not use brake fluid.  Sound like I can use either a little Dextron 2 ATF, Dextron 3 ATF, shock absorber fluid, or neatsfoot oil.  I will probably go with the neatsfoot oil as the safest bet. The help is much appreciated.

Dave