The Castair F-10D-038 is a complete intake air filter assembly for piston compressor pumps with a 3/8" NPT inlet port. It threads directly onto the pump head intake port, filters incoming air through a paper element (the 10D element), and quiets the intake noise that unprotected pump inlets generate. If your Castair pump has a 3/8" intake port and the filter is damaged or missing, this is the replacement assembly.
What This Filter Does
Every piston compressor pulls in shop air on each intake stroke. In a working garage or industrial shop — concrete dust, metal particulates, oil mist, general airborne debris — that unfiltered air reaches the cylinder walls and valve seats directly. The F-10D-038 installs on the pump intake port and removes particulates before they can cause abrasive wear inside the compression chamber.
The compact housing also acts as an intake silencer, reducing the sharp intake pulse noise that bare pump ports produce.
Key Specifications
- Part Number: F-10D-038
- Inlet Size: 3/8" NPT
- Outer Diameter: 3.25"
- Overall Height: 3.50"
- Flow Rating: 12 CFM
- Filter Element: 10D paper element (replace separately)
- Construction: Cast iron
F-10D Series — Available Configurations
The F-10D series offers the same housing in three inlet thread sizes, all rated at 12 CFM with the same 10D replacement element:
- F-10D-025 — 1/4" NPT inlet
- F-10D-038 — 3/8" NPT inlet
- F-10D-050 — 1/2" NPT inlet
All three use the same 10D element, which simplifies parts stocking. For larger pumps requiring 1/2" through 1-1/2" inlets in the 20-60 CFM range, see Castair's S-16D and S-20DP silencer-filter series.
When Does a Shop Need This
- Replacing a broken or degraded filter assembly on a Castair pump with a 3/8" inlet port
- The filter element seat is damaged and the paper element will not seal
- Rebuilding a Castair pump and need a new complete intake assembly
- Intake noise has increased noticeably — often indicates a missing or deteriorated filter housing
The 3/8" NPT inlet is a mid-range size in the Castair pump lineup. Measure the pump's intake port threads directly to confirm before ordering.
Replacement Element
Use the Castair 10D paper filter element for service. Replace on a schedule based on your shop environment — dusty conditions require more frequent element changes. A clogged intake element restricts airflow, increases pump temperature, and accelerates wear. Stock a spare 10D element so filter service does not mean downtime.
Why Buy From OEM Diagnostic Tools?
OEM Diagnostic Tools has supplied professional shop equipment and components since 2016. We carry Castair parts so you can get the right intake filter without hunting through distributor channels. Free shipping on qualifying orders, free tech support at 866-217-0063, and full manufacturer warranty. Call us if you need to verify the inlet size for your specific pump before ordering.
Call 866-217-0063 for quick answers and help!
