Question about air compressor oil?

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What is the difference between SAE 30 non detergent motor oil and 30 weight air compressor oil? I'm just wondering because the motor oil is cheaper.
 
The basic non-detergent is suggested because the detergent will absorb moisture and the compressor never gets hat enough to evaporate it. So a non-detergent lets the moisture settle out where you can drain it and it can't get into working parts.

What you need is an ISO 100 R&O compressor oil. Should be available in a lot of brands/stores. And should be cheaper than motor oil.
 
I thought non detergent oil for lawnmowers and compressors was to make the oil 'stick' better to surfaces, and allow additives to work better.
As to heat, believe me, compressors get hot.
 
Originally Posted By: johnsmellsalot
What is the difference between SAE 30 non detergent motor oil and 30 weight air compressor oil? I'm just wondering because the motor oil is cheaper.


John,
The replies posted thus far may be sufficient and I wouldn't know the answer to this question myself but, to broaden your viewers(if you haven't already), you may also want to post this same question in the "Lawn Mower/Small Engine" Section
 
I bought a compressor & it came with some synthetic compressor oil. It was enough to fill it to the correct capacity. With the little bit required I'd just get the correct oil. I consider it something you fill and it's good to go for a fair amount of time.
 
Originally Posted By: mechtech2
I thought non detergent oil for lawnmowers and compressors was to make the oil 'stick' better to surfaces, and allow additives to work better.
As to heat, believe me, compressors get hot.


Additives? Non-detergent oil doesn't have any additives. And it's definitely not suitable for lawn mowers.
 
Originally Posted By: boraticus
Both of my compressors manuals specify Mobil 1 5W30.

What? I own 11 gas powered air compressors. All honda's with either v-twin or inline twin pumps. They spec 5w-30 oil for the engines and non-detergent 10 weight for winter and non-detergent 20 weight for summer. And they all call for oil changes every 100 hours.
A 5w-30 will foam up in a compressor pump. I have seen it happen. And foamed up oil really doesn't lubricate well,does it.
Op. A non detergent oil is what you want. I switched over to amsoil's compressor oil due to it's cold flow properties in winter and it lasts longer.
 
I don't know what the difference between the 2 oils are but if it's for an indoor use compressor either will work fine. If you are using it outside buy the thinnest oil you can find. Until the weather warms up anyway
 
I agree. Since the oil capacity is only 5 ounces and the oil change intervals are twice a year, I'm just going to use the compressor oil. It costs a little more than regular non detergent oil. Maybe the compressor oil has something that regular oil doesn't.

My compressor is a 21 gallon Central Pneumatic from Harbor Freight. It didn't come with oil so I drove to Sears and bought some Craftsman 30 weight compressor oil before firing it up.
Originally Posted By: Mr_Joe
I bought a compressor & it came with some synthetic compressor oil. It was enough to fill it to the correct capacity. With the little bit required I'd just get the correct oil. I consider it something you fill and it's good to go for a fair amount of time.
 
Originally Posted By: Clevy
Originally Posted By: boraticus
Both of my compressors manuals specify Mobil 1 5W30.

What? I own 11 gas powered air compressors. All honda's with either v-twin or inline twin pumps. They spec 5w-30 oil for the engines and non-detergent 10 weight for winter and non-detergent 20 weight for summer. And they all call for oil changes every 100 hours.
A 5w-30 will foam up in a compressor pump. I have seen it happen. And foamed up oil really doesn't lubricate well,does it.
Op. A non detergent oil is what you want. I switched over to amsoil's compressor oil due to it's cold flow properties in winter and it lasts longer.


This is the excerpt from my air compressor operators manual:

"For this compressor, use 250 mL / 8.4 oz of ISO100 (SAE 30), non-detergent compressor oil, or Mobil 1 5W30 synthetic.
Do not use regular automotive oil such as 10W-30. Additives in regular motor oil can cause valve deposits and reduce pump life. For maximum pump life, drain and replace oil after the first hour of run time."

I chose Mobil 1 5W30 because my compressors are kept in unheated garages. Makes them easier to crank up in winter. With the original straight 30 oil, they were very hesitant to turn over at below zero temps. Now they spin up right away.
 
I've always used what ever oil I had in the garage the few times I've had to fiddle with small portable air compressors. Most likely 10w30, 5w30 or SAE30.

I personally would never stress over trying to locate a non-detergent oil.

If it was a super high dollar commercial compressor, I'd be more inclined to use what the manufacturer suggests.

Joel
 
I've had valve deposit problems with 40 wt. diesel engine oil (high detergents) in some 20 hp compressors I was running. A change to an industrial oil (similar to a heavy hydraulic oil) worked great. It all depends on what the compressor maker wants. In some 50 hp, 450 psi compressors, 32 viscosity rust & oxidation inhibited (R & O) oil was the right stuff.

I agree about the detergent oil holding water in emulsion, but a non detergent oil that lets the water settle out needs to be drained--both do when water accumulates. The settled out water, if allowed to accumulate in excess, means that on start up the compressor will be lubed with water instead of oil.
 
I get water in my pumps. Turns the oil a grey colour. I had some amsoil compressor oil leftover from summer however I just buy the cheapest stuff there is and change it every 2 weeks with the engine oil.

And as for the above post about using mobil 1 5w-30. How is it different than engine oil. It is engine oil. Again. Mobil paying a manufacturer to specify their product. Nothing new
 
Originally Posted By: Clevy
I get water in my pumps. Turns the oil a grey colour. I had some amsoil compressor oil leftover from summer however I just buy the cheapest stuff there is and change it every 2 weeks with the engine oil.

And as for the above post about using mobil 1 5w-30. How is it different than engine oil. It is engine oil. Again. Mobil paying a manufacturer to specify their product. Nothing new


Yes it's Mobil 1 5W30 synthetic engine oil. My manual specifies it and it seems to work just fine. Straight 30 doesn't like to be stirred at twenty below F.
 
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