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Why is there oil in my rotary screw air compressor tank?

Is oil okay in my tank?

Don’t be alarmed if you find oil in your air compressor tank. Actually, all rotary screw compressors pass trace amounts of oil in the compressed air. The question is how much is the normal amount of oil in my compressor tank?

Normal oil carry-over

Coalescing filters play a big role in keeping the oil out of your tank. Depending on the upkeep, maintenance and overall condition of the compressor will depend on how much oil is being passed along downstream. A trace amount of oil may appear in your tank, which is a normal amount typically seen and nothing to be alarmed about.

Excessive oil in your tank

If you have oil actually “pooling” in your tank, you may have a few things going on with your compressor. Your separator may be saturated, punctured or even collapsed which is creating excessive oil carry over. Additionally, if the scavenger lines or check valves are plugged and not working, that will create excessive oil carryover.

Routine Checks to Help:

- Record the differential across your separator. - Stay up on routine separator maintenance. - Use Original OEM separator which is designed to remove the most oil carry over. - Regularly drain your air receiver tank.

Jim Phillis

You ask, we answer. Visit our Expert Corner for every #CPTechThursday to find answers to common industry questions and highlights of CP's high-quality compressors. We love providing our customers with answers to their technical questions.

Jim Phillis , Technical Support Chicago Pneumatic

Please contact [email protected] for any questions about maintenance kits or parts. For tech support for any Chicago Pneumatic product, please call us at (877)861-2722, opt 1. Or email us directly at [email protected] . We look forward to helping.

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