Troubleshooting the Ingersoll Rand P185: Lubricating and Cooling Oil Flow System
If your P185 or XP175 is leaving oily surprises where it shouldn’t—or running hotter than it should—you might be dealing with a lubricating and cooling oil flow issue. This guide covers common problems and solutions for Ingersoll Rand portable compressor models P185A-SJD, P185A-WJD, XP175A-SJD, and XP175A-WJD to help you diagnose and fix the issue quickly—no service call required.
1. Excessive Oil Carryover into Air Discharge
Issue: If you’re seeing oil in the discharge air or downstream tools, your machine may be experiencing oil carryover.
Possible Causes:
- High oil level
- Improperly installed separator element
- Clogged oil scavenger line
- Leaking or worn oil seal
- Ruptured separator element
- Plugged orifice in scavenger line
- Defective minimum pressure check valve
- Improper unit shutdown
Solution: Start with the basics—check the oil level and separator element installation. If issues persist, inspect the oil seal, scavenger line, and pressure check valve for damage or debris.
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Shop oil scavenger lines
Shop oil seals
Shop minimum pressure check valves
2. Oil Seal Leaks
Issue: You’re finding oil where it shouldn’t be—around the seals.
Cause: Contaminated lube oil can cause your seals to break down faster than they should.
Solution: Replace the oil seal and flush out the contaminated oil. Always use high-quality compressor oil that meets spec.
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Shop approved compressor oil
3. Oil Blowing Back into the Air Cleaner
Issue: You’re seeing oil in the air intake path—never a good sign.
Possible Causes:
- Damaged unloader valve or seat
- Missing or damaged unloader valve spring
- Damaged unloader valve bushings
Solution: Check the unloader assembly for wear or missing parts and replace as needed.
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Shop unloader valve springs
Shop unloader valve bushings
4. Compressor Overheating
Issue: If the unit is running hot or shutting down due to high temps, it’s time to dig into the cooling system.
Possible Causes:
- Dirty or clogged oil filters
- Low oil level
- Wrong oil grade or type
- Defective oil temperature bypass valve
- Incorrect oil cooler piping
- Inadequate oil flow
Solution: Check and replace oil filters regularly, ensure proper oil levels, and verify that you’re using the correct oil. If the problem persists, inspect the bypass valve and oil cooler setup.
Shop oil filters
Shop oil temperature bypass valves
Shop approved compressor oil
5. Engine Runs Backward on Shutdown
Issue: Upon shutdown, the engine briefly spins in reverse. That’s not just weird—it can be damaging.
Possible Causes:
- Damaged unloader valve or seat
- Missing or damaged unloader valve spring
- Damaged unloader valve bushings
Solution: This usually comes back to the unloader assembly. Replace damaged or missing components to prevent blowback and ensure clean shutdowns.