DIY Oil Filter Change for Ingersoll Rand P100–P185 Portable Compressors
Don’t let a clogged oil filter sneak up on you. Ingersoll Rand compressors—models P100-WDJU, P125-WJDU, P160-WJDU, P175-WJDU, and P185-WJDU—are equipped with spin-on, throwaway oil filters that keep the lubrication and cooling oil clean. When these filters get dirty, your machine keeps running—but the oil stops getting filtered. That’s a problem you can avoid with this simple maintenance step.
How the Oil Filter Works
This system uses a spin-on filter with an internal bypass valve. When clean, all oil flows through the full filter element. But as dirt collects on the outer surface, pressure builds up inside the housing. Once the pressure differential hits 15 psi, the bypass valve opens—allowing unfiltered oil to keep the system lubricated. The longer you wait, the more oil bypasses filtration altogether.
Bottom line: if you're in bypass mode, your oil is no longer being filtered. That’s a recipe for wear, overheating, and long-term damage.
Recommended Oil Filter Service Intervals
- Replace the filter after the first 50 and 150 hours on new or overhauled units
- After that, replace the filter every 500 hours of operation
Step-by-Step: How to Change the Oil Filter
- Shut down the unit and let it cool.
- Open the service air valve(s) to relieve system pressure, then close the valve(s).
- Clean the filter exterior to prevent dirt from entering the system during removal.
- Remove the old filter by turning it counterclockwise. Inspect and discard it.
- ⚠️ Note: If you notice varnish, shellac, or lacquer buildup on the element, your oil may be breaking down. Change the oil immediately.
- Inspect the gasket contact area on the housing. Clean and repair if needed.
- Install the new filter by hand. Turn it clockwise until the gasket makes contact, then tighten an additional 1/2 to 3/4 turn.
- Start the unit and allow it to build pressure. Check for leaks before placing the unit back in service.
Wrap-Up
A fresh oil filter is your first line of defense against wear, overheating, and expensive repairs. Stick to the service schedule and keep your compressor running like it should.