Overview
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 — item 2
- HydraMaster Boxxer 423S
- HydraMaster Boxxer 318
- HydraMaster Titan 425
- HydraMaster MAXX 450D / 470D / Diesel — item 3
- HydraMaster CM402
The Bridgepoint parts catalogue cross-references it for the SpitFire 4.0, MAXX 550, MAXX 450D, MAXX 470D, Boxxer 421, Boxxer 427 and the Javelin, which matches CCW's own record.
Important — orifice size is not a tuning adjustment
HydraMaster fit more than one orifice size, and the machine was designed around the one it left the factory with:
- 180-004 — 0.033 inch (this part)
- 180-006 — 0.061 inch (not currently a stocked CCW line)
- 180-030 — 0.021 inch, 1/8" NPT stainless, listed for the Boxxer 323HP
Several machines are built with both a 0.033 and a 0.061 orifice in the same manifold, doing different jobs. Note which position you are working on before you remove anything, and fit the same size back. Changing orifice size changes flow, pressure behaviour and heat, and it is not a way to make a machine perform better than it was designed to.
What goes with it
- 052-423 — Bushing, Modified Set Screw Orifice, the housing this screw sits in
- 049-016 — replacement screen for the ¼ inch Y strainer, the filter that protects it
Service advice
A partly blocked orifice is one of the most misdiagnosed faults on a truckmount. It reads as low flow with normal or high pressure, and operators go looking at pumps.
Do not clear an orifice with wire, a drill bit or anything that can enlarge it. Once the hole is bigger than 0.033 inch the part is scrap and the machine will never read right again. Solvent, ultrasonic cleaning or a new orifice are the answers.
If it blocked once, look upstream. A blocked orifice means the Y strainer screen let something through.
Frequently asked questions
Can I fit a bigger orifice for more flow?
No. The machine was designed around this size. Changing it changes pressure, flow and heat together, and rarely in the direction you want.
How many does my machine take?
Usually one 0.033 inch, and on several machines a 0.061 inch as well in a different position. Check the assembly drawing for your model.
Can I clean a blocked orifice?
Yes, chemically or ultrasonically. Never mechanically.
Does it include the bushing?
No — the housing is 052-423, a separate part.
Working on a Hi-PSI manifold? Send us your machine model and serial number and we will check the assembly drawing for the correct orifice sizes and positions before you order.
