New compressor - oil leaks through breather

Sir,
Presently i am validating my new high speed(1435rpm) direct drive(5HP)compressor. i found within few hours of running oil is coming out of breather which is mounted on the end cover. Could you please give me possible causes of oil leak.
Thanks

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Bill answers...

Howdy, and thanks for writing in.

Nope, oil shouldn't be coming out of the breather.

Even if it's bypassing the seals on the piston, the intake valve should prevent any oil (or air for that matter) from exiting through the breather.

Given that it's a new compressor, I surmise that there was excess oil in the piston, also in the intake valve, and that's what you are seeing.

Monitor the sump oil level for a while as the compressor runs. If the oil level doesn't drop, then the oil isn't coming from the sump and I expect it to stop leaking from your breather.

It would help if I knew how much oil, and is the quantity decreasing or increasing?

If the oil leak persists, it would seem to me that you've possibly three problems.

The sump was overfilled, you've got oil blow-by of the piston seals, and your intake valve is leaking.

Cheers,

Bill