Oil turns black quickly. Do I need to worry

[John Hansen]

hello!

I have a Paramina Mistral M6-BZS gas powered scuba compressor purchased new last year. Only used it for 10 hours.
It seems that in a matter of hours the oil (synthetic) turns grey/black. In the sightglass it seems clearer but the imaged attached shows the drained oil. (the water drops are from rain)

I asked my supplier and was told this is normal due to the sightglass exposing the oil to light. I can't see any debris in the oil but it got me worried.
Compressor is performing normally.

 

[RayfromTX]

Have you had the air analyzed? I would be concerned as well.

 

[John Hansen]

We use this compressor for paintball activities, so it will not be used for breathable air. It would have been an even greater concern if not.
I am not sure what turns the oil so dark quickly. I would have understood it if if was a diesel engine but since there is no combustion i wonder why. I might try contacting the manufacturer directly.
Drain water is milky white which is normal according to manual.

 

[Wookie]

If the oil is black, it is doing it's job removing carbon. So, where is the carbon coming from? The usual answer is the oil, because it's running too hot, and the oil passing through the rings is caking on the valves.

A compressor with 10 hours shouldn't have had time to carbonize the valves, and it shouldn't be leaking oil either. I am not familiar with a Paramina, so I can't help with specifics, but did you break it in by following the manual? Every compressor I've ever bought new required a mineral break in oil for the first 50 hours. Now, I know Bauers no longer require this, but what does the Paramina require?

 

[John Hansen]

Thanks

Nothing in the manual mentions anything about running with different oil for break-in. I have read it page by page many times to make sure I understand this machine.

-"Change the oil after the first 20 operating hours and then every 500 hours"
-"The compressor unit is delivered filled with PARAMINA HPS OIL p.n.112001000 (Synthetic oil)"

I guess it could be the oil itselt running hot. There is a oilpipe with an inline filter from the block to the 1st stage behind the intake filter. I guess this feeds oil mist to the 1st stage for lubrication.

Manual here: https://1drv.ms/b/s!AqOmyrOjtI5RiDcuwTNeAggifkfD

 

[Wookie]

What is the ambient temperature where the compressor is running, while it's running? Where does the intake feed from, and how much suction pipe to the outside have you given it?

 

[John Hansen]

Temp outside is around 20C/68F. Only using the 2 metre included suction to the air filter. Trying to avoid exhaust gases as much as possible. Will check air filter later today.
The compressor is only used outside and in the open.

The supllier says the oil is normal... but I would not run on the same oil for 500 hours...

 

[Wookie]

Well, you're getting break in sludge in the oil. If you are really worried, send the oil for analysis. There are 25 things that could make the oil turn black, only a few of them are really bad. I would run for another 10 hours and change and watch the oil again.

 

[BDSC]

The supllier says the oil is normal... but I would not run on the same oil for 500 hours...

A good synthetic oil will last 500 hours. Maybe longer.

 

[rcontrera]

That could actually be from using too thin if an inlet hose. There are a few paintball shops/distributors that are selling compressors without fully understanding them. If your compressor is having to suck on a straw to get air, the first stage is going to heat up dramatically and cook your system. Try changing the oil and get rid of the inlet hose.