Compressor Oil

OK, I know, "beating a dead horse" etc. etc. However, I've been wondering, and would like comments. I have a feeling that some of these high dollar oils are tweaked more towards the "breathing air" aspect, rather than to the "long life" aspect. In other words, I wonder if there is something better to run, "if" we don't really need "breathing air quality". I used Royle Purple in my Yung Hengs, no problems. Used the $35/40per liter Coltri oil in a DAVV 4 cylinder, and had the 4th stage freeze up. Now running the same oil in my new 3 cylinder Daystate, so far, so good. Just wondering, that's all.

https://www.coltri.com/en/news/187/benefits-of-coltri-oil-st-755-and-original-components/
 
Hello,

I have an LC-110 I purchased from AOA. I saw your thread earlier about how it was packaged, amazing isn't it?!? I am of the belief of picking an oil and sticking to it. I have about 12 hours or so on my LC-110 and it shipped with CE-750 and all it's seen is CE-750. I "hoarded" about 2 liters of CE-750 from Nuvair.

My beliefs are oversize the compressor, undersize the load, and stick to one oil type. :)

If yours shipped with CE-755 then your answer is Coltri CE-755 :) BTW, I use CE-750 in my LPA YH, it's a YH just doesn't have the HPA stage-2 head. It's got the stage 1 head as a basic shop compressor.
 
And the story continues..... so I was running the Coltri CE 750 in my DAVV 4 cylinder compressor, when it froze up, while running. Now that oil is no longer available ??? WHY ??? is that why my compressor froze up ??? I have a new 4th stage cylinder and piston coming from China ($350) to rebuild my DAVV, and will use the ST 755 that came with my new Daystate compressor. Sooooo confusing, this oil thing. I also have the Coltri CE 750 oil in my Carette compressor. I'm wondering now, if I should dump it, and refill with the ST 755 ???
 
I doubt it? I've got 12 hours on mine and I've only used CE-750. What was your duty cycle and load? I've shared images of my coalescing tower and the oil is quite pretty with no debris. I'm only topping off a 90 cu-in bottle so my run time is 2 minutes warm up, 5 minutes or less filling, 2 minutes cool down.

How much oil did you add? I use a measured 330mL. You do the warm-up and cool-down during fills?

Looks like CE-750 is indeed dead, I "hoarded" enough to get me to about ~70 hours or so on the compressor before I have to figure out what to do.

I'd go with what AOA told you, they're the US distributor for the LC-110s.
 
Yes, I do all the recommended things, like warm up, shut down, etc. etc. The DAVV had very little time on it, when the 4th stage froze up. Like many others, it's just a rod in a sleeve. No rings of any kind. A very precise fit. Took awhile to get the rod out of the sleeve, and after cleaning up, could not get it to fit. Almost seemed as if the sleeve had gone egg shaped. I used some fine sand paper on a stick, and finally some valve seating compound, and got it working smoothly. But now it won't go over 1500psi. I also had a similar failure on the high pressure stage of my Carette. Same thing, just a rod in a sleeve. It didn't freeze up, but got worn enough that it wouldn't go over 3000psi. A new piston and sleeve fixed it, so far. I hope to be able to get my DAVV going again, with a new 4th stage, that might arrive today! If it does arrive, I'll be totally surprised, as I just ordered it last week, and it showed as coming from China. But, DHL just called me, wanting my home address, so who knows? Kinda like the election huh? Ha!😄
 
Hah! Yeah, I got no idea. Wonder why CE-750 got deprecated in favor of 755.

CE-750:

Appearance 20°C: Clear yellow liquid
Water content (ASTM D-6304): 0.03
Kin visc @ 40° C (ASTM D 445): 139.0 cST
Kin visc @ 100° C (ASTM D 445): 13.0 cST
Viscosity index (ASTM D 2270): 84
Total acid number (ASTM D-664): 0.12 mg KOH / g
Temperature minimum operating (ambient): -15° C

ST-755

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