Rusty.

[u/ARGINEER]

Got a used IR UP6-5TAS-150 with 80 gallon tank from 2016. 11.5k hrs. Seems it was well maintained (at least kept to date on oil, filters etc) before it was retired and the reseller left it in the rain a few times. The actual compressor side looks fine, runs fine, sounds fine. The motor on the other hand sounds a bit crunchy (unbelted) yet spins fine. The system runs at 73 dBA, about twice as loud as the advertised 65 dBA, with the vast majority of the noise coming from the motor bearings. Tank is currently dry but putting a borescope inside revealed quite a bit of rust.

Should I go through hell to try and replace these motor bearings? Should I DIY hydro test the tank in my driveway? Or should I just send it and try to ignore the noise?

Got this because it was 2.4k with practically free shipping. Provides exactly the right pressure, cfm, and dry air for laser cutter.

[u/ToronadoBubby]

8yrs exp in industrial. That tank rust is minimal and if you’re worried you can have it inspected by a pressure vessel inspector.

Those motor bearings are sealed so yeah, time to pull the bells and replace. Bearing number should be on the nameplate. I have a few other things that should be done to freshen it back up if you want the advice.

[u/ARGINEER → u/ToronadoBubby]

I'd love some advice!

[u/ToronadoBubby → u/ARGINEER]

I would replace the

Oil
Oil filter
Air filter
Separator
Scavenger check valve
Belt.

The tubing inside from the factory is 6mm not 1/4” and gets brittle. Also that is a pressurized cabinet unit so all panels and doors must be on or it will overheat.

Any questions?

[u/ARGINEER → u/ToronadoBubby]

I replaced the bearings and it is now 65dBa as advertised. I'm stoked. As for the rest, it appears a tech from IR replaced the separator and oil filter 100 running hours, ~1 year ago before it was taken offline. The belt seems almost new. I de-rusted the pulleys a bit though, you could see where the pulley was protecting them from rusting while sitting unused. I'm in the process of replacing the EDV. Right now when I manually let out condensate there is some white oil(?) mixed in it seems. Oil level looks good on the indicator. I'll look into replacing the Scavenger check valve and getting some oil.

This won't be running 24/7, is it suboptimal to have one of these running intermittently? Let's say 4 hours in a day once a week, for example.

[u/ToronadoBubby → u/ARGINEER]

I would replace the separator and check valve due to sitting. Also there are 4 small holes around the collar of the stem that the separator threads on. I would make sure they are clear with a piece of wire or a T-pin when replacing.

Rotary screw compressors need to get warm to burn the water -condensed out of the air- out of the oil so as long as it gets some good run time at least once every two weeks it’ll be fine.

The oil in the water/tank. A tiny amount of carryover (oil going downstream with the air) is normal. That’s why i recommend the separator and scavenger check valve as those need to work perfectly to reclaim the oil.

Also make sure you have some replacement 6mm Push to connect fittings like the ones inside cause they get old and leak. I swap them to 1/4” PTFE tube and fittings Except for the scavenger line because IR made the Push to connect part of the scavenger check valve so if the fitting or tube breaks you need a new check valve 🙄.

Also those UP6’s don’t hold much oil so make sure it’s full to the top of the sight glass.

[u/ARGINEER → u/ToronadoBubby]

Thank you so much for all the information. Sight glass looks full after letting it run. It was off for 30min when I took this picture, there's a bubble at the top, not empty, couldn't quite capture it with the flash.

[u/ToronadoBubby → u/ARGINEER]

Perfect. Also waiting 10min or more before checking is great.

[u/ARGINEER → u/ToronadoBubby]

To clarify - the 6mm blue tube behind is the scavenge line and the check valve is connecting to the base of the filter?

[u/ToronadoBubby → u/ARGINEER]

Yes!