Orifice Regulator SF4.0 Set Screw Base UOM:EACH and the first symptom is

and the first symptom is usually lost vacuum at the heads rather than anything visible at the hub itself

and the machine was designed around the one it left the factory with:

pressure behaviour and heat

Look for rounded or chipped vane tips

• New optimised outlet valves

Orifice Regulator SF4.0 Set Screw Base UOM:EACH and the first symptom isOverview Set screw orifice, 0. 033 inch. HydraMaster part number 000 180 004, listed as Orifice, Set Screw 0. 033" and, in some assemblies, as the primary orifice. It is a precisely sized hole in a set screw, and it is what meters solution flow through the high pressure manifold. The 0. 033 inch is not a nominal figure it is the specification. What it fits Named in the Hi PSI manifold assembly of: HydraMaster Boxxer 421 item 3 HydraMaster Boxxer 427