Non detergent oil for air compressors?

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So, as I understand it: Non detergent oil is used in air compressors because the moisture will settle to the bottom of the drain vs. emulsifying. Seems to make sense to me. Now, here's the confusion. My compressor, a Kobalt 30 gallon compressor, has a sticker on the side that says non-detergent oil. In the product manual, it specs out either Kobalt's own oil, or Mobil 1 synthetic 10w-30. So... This begs the question: Why would they recommend a passenger car oil while warning of "regular automotive oils" in the user manual? It still doesn't add up with the non-detergent oil labeling on the side. What's different about Mobil 1 in this application?
 
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Your compressor was engineered using Mobil 1 engine oil, the world's leading #1 synthetic oil. Tests have shown that more compressors run on Mobil 1 engine oil have their serviceable life extended two to seventy times vs compressors running the next leading synthetic oil. wink
 
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When i bought the Quincy the service guy told me it only needs the most basic oil, the additives found in engine oils are of no benefit to it. On the other hand he didn't say those additives would harm it either, i cant see how it would either but i deferred to their recommendation.
 
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I use 30wt nd napa brand oil from napa. Its cheap and i have run my compressor hard and hot and the oil has never failed.
 
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Originally Posted By: jrustles
Your compressor was engineered using Mobil 1 engine oil, the world's leading #1 synthetic oil. Tests have shown that more compressors run on Mobil 1 engine oil have their serviceable life extended two to seventy times vs compressors running the next leading synthetic oil. wink
You can't be serious. OP I've got 16 5.5hp Honda powered air compressors. I've NEVER used a detergent oil in them. I use only amsoil compressor oil because of the conditions these pumps operate in. From 30c to -40c we are working and amsoil stays fluid at those cold temps. The engines get supertech because I need 5 gallon pails because I've got so many compressors to service. Use only non-detergent oil in the pump. I've seen guys use regular oil and the stuff foams up once any moisture gets in the oil. Foam isn't a good lubricator.
 

SnowDrifter

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^^Makes sense. But I still don't understand why they say non-detergent and Mobil 1 in the same breath
 

JHZR2

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Originally Posted By: Trav
When i bought the Quincy the service guy told me it only needs the most basic oil, the additives found in engine oils are of no benefit to it. On the other hand he didn't say those additives would harm it either, i cant see how it would either but i deferred to their recommendation.
I can understand that angle - only an "R&O" add pack is needed/desired because of the basis of operation. The fact that the detergents are the means of emulsifying water in the oil is news to me.
 
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I am on a 25 yr compressor oil change cycle. I changed it this year and last time was in the 1980s (give or take), actually that was when it was new. Its 5HP two stage that does not see a while lot of use. The issue is I am 61 and thus the next oil change will be when I am 86.
 
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Originally Posted By: JHZR2
Originally Posted By: Trav
When i bought the Quincy the service guy told me it only needs the most basic oil, the additives found in engine oils are of no benefit to it. On the other hand he didn't say those additives would harm it either, i cant see how it would either but i deferred to their recommendation.
I can understand that angle - only an "R&O" add pack is needed/desired because of the basis of operation. The fact that the detergents are the means of emulsifying water in the oil is news to me.
I am not sure what the additive is or what oil has it, but Mercruiser gear oil has an additive to hold water with the gear oil and not let it settle out. I believe it just holds it in suspension. Not being a chemist, I am not sure of the difference between emulsify and suspension. Darn another question my Dad could answer. I miss him.
 
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Originally Posted By: bubbatime
Detergent oils will foam up when agitated. Foam doesn't lubricate very well, and is why non-detergent oil is recommended.
Sorry for creating a zombie thread. How does the action of a compressor "agitate" oil and that of an internal combustion engine NOT agitate oil? I must be misunderstanding something. Don't motor oils have anti-foaming additives?
 
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I've heard the detergents in regular motor oil had a tendency to form carbon deposits on the reed valves. There should be some silicone in non-detergent oil to keep it from foaming. I've used M1 0W-40 in a Hitachi compressor calling for 5W-50 synthetic - compressor worked but it was on its last legs.
 
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Originally Posted By: Clevy
Use only non-detergent oil in the pump. I've seen guys use regular oil and the stuff foams up once any moisture gets in the oil. Foam isn't a good lubricator.
That's the answer right there. Hey wait a minute, Clevy is back? shocked2
 
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Originally Posted By: SnowDrifter
So, as I understand it: Non detergent oil is used in air compressors because the moisture will settle to the bottom of the drain vs. emulsifying.
I don't buy that or the "foaming" because I've proven to myself over time it never happens. I purchased a new Campbell Hausfeld air compressor from Farm & Fleet, back in Illinois in 1987.... 30 years ago. It get's only occasional use, and is kept in an unheated and non air conditioned garage. The first winter I had it when the temperature got cold, (below freezing), the oil that the factory put in the compressor would thicken to the point that it would trip the breaker on the electric motor, because it couldn't get going. So I drained all of the oil out, and refilled it with Mobil 1 0W-20 Motor Oil. That oil immediately solved the problem, and the motor had zero problem running up, all the way down to below zero temperatures. That oil has stayed in that compressor crankcase up until last year. When I changed it out, it drained out as clean and clear as when I put it in. I refilled it with the exact same type of oil. The unit still runs like it did when I first bought it. That convinced me that all of this non detergent oil requirements didn't mean a thing in actuality. At least in air compressors where no combustion ever takes place.
 
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Originally Posted By: billt460
Originally Posted By: SnowDrifter
So, as I understand it: Non detergent oil is used in air compressors because the moisture will settle to the bottom of the drain vs. emulsifying.
I don't buy that or the "foaming" because I've proven to myself over time it never happens. I purchased a new Campbell Hausfeld air compressor from Farm & Fleet, back in Illinois in 1987.... 30 years ago. It get's only occasional use, and is kept in an unheated and non air conditioned garage. The first winter I had it when the temperature got cold, (below freezing), the oil that the factory put in the compressor would thicken to the point that it would trip the breaker on the electric motor, because it couldn't get going. So I drained all of the oil out, and refilled it with Mobil 1 0W-20 Motor Oil. That oil immediately solved the problem, and the motor had zero problem running up, all the way down to below zero temperatures. That oil has stayed in that compressor crankcase up until last year. When I changed it out, it drained out as clean and clear as when I put it in. I refilled it with the exact same type of oil. The unit still runs like it did when I first bought it. That convinced me that all of this non detergent oil requirements didn't mean a thing in actuality. At least in air compressors where no combustion ever takes place.
So... you live in Arizona, and you make blanket judgments about all air compressors (and their oils) handling humidity that same way yours does. OK.
 
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Originally Posted By: nthach
I've heard the detergents in regular motor oil had a tendency to form carbon deposits on the reed valves. There should be some silicone in non-detergent oil to keep it from foaming. I've used M1 0W-40 in a Hitachi compressor calling for 5W-50 synthetic - compressor worked but it was on its last legs.
I think there's some truth to this. I have a small Craftsman for pumping up tires or a nail gun. Changed the oil to Castrol HD30 a number of years ago. It did as you say muck up the reed valve. Ironically I lubed it up with the same oil and to this day it still works. I think I need to change it out to something thinner though. Since moving back North, in the cold it does not want to get going very easy.
 
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