[TheForge] Air compressor question

[Justin Fellenz]

Bob,

Air compressor oil is non-detergent oil. All motor oils have detergents
in them, which mixes (I'm told) with the moist air blow-by that happens
in a compressor and decreases the effectiveness of the oil. I suspect
there are also moisture-resisting compounds in air compressor oil
similar to those in marine oils, because compressors just move air
around and don't try it by heating much or burning anything. 

If you can find a non-detergent 30 weight that'll work, or 30 weight
vacuum pump oil. But Grainger sells Mobil Rarus 427 for reciprocating
compressors and will ship. The link is here:

http://www.grainger.com/Grainger/productdetail.jsp?xi=xi&ItemId=1611689577&ccitem=

I use it in my compressor with good luck, and a friend of mine with a
big multi-man shop uses it in his with the same results. If you don't
run it too much, change it once a year (one man shop, weekend use). In
the big shop the oil gets changed about every couple of months.

A good 3hp 175 psi machine with 80 or 120 gal should keep one man in
air. You can always daisy-chain tanks together to keep the head from
running as often.

Cheers,

JRF

--- Bob Ehrenberger <eforge at centurytel.net> wrote:
> I know this goes around the list every now and then. But I didn't
> have a
> need until now.
> 
> I had a friend give me an old air compressor when he got a new one. 
> It's
> only 3hp, but better than the jury rigged one that I have been using.
> 
> I checked the oil, it was a little low, but black as coal.  I want to
> change
> it.  Can I use motor oil or do I need to get something specific for
> compressors?  I don't have a lot of options locally all we have is a
> farm
> supply store (Orscheln's).
> 
> Robert Ehrenberger
> Shelbyville, Mo.
> 
> 
> _______________________________________________
> Manage membership or unsubscribe at:
> http://mailman.qth.net/mailman/listinfo/theforge
> theforge mail list group photo site is
> http://www.photoaccess.com
> Login:  blacksmithblacksmith at hotmail.com
> password:  anvil
> ___________
> 
> 
>