oil for Sears air compressor

[2K2AcuraTL]

(after a search on the boards)
Not sure if this is the correct board to post this, but here goes.

I have my fathers old (15 years+) Sears air compressor, twin cylinder, 110v, 5 gal tank.
My dad has never changed the oil in this unit.
I changed it last year with M1 15w50 (try-synth).
Not sure if that was the right choice of oils...!!!

Let me know if I need to change it again.
Thanks
Jean

[ January 23, 2003, 04:35 PM: Message edited by: 2K2AcuraTL ]

 

[satterfi]

That wasn’t the best choice of oils but I doubt you’ll hurt anything. Motor oils have additives you don’t need.

For a piston air compressor you should use non-detergent straight 30w with anti-foam additives. Companies make oil specific for air compressors. Good luck finding it small quantities though.

I use Redline MTL when I need a 30w non-detergent oil.

 

[Hirev]

IMHO oil should be thinner. I have a 20 year oil Sears twin cylinder. The owners manual says to use straight 20wt Non Detergent. I have not been able to get this in many years. I use Campbell Hausfeld Air compressor oil anymore very thin also. Home Depot Has it.

 

[MolaKule]

Most reciprocating compressors I have come across specify an ISO 32 or 46 oil, which is SAE 10 or 20 weight. My CH has a 10 gallon tank and a 4.0 hp motor.

 

[Bror Jace]

We also have a Sears/Craftsman electric air compressor. It's a good sized one but off the top of my head I can't tell you what the motor or tank sizes are ... 1hp? 1.5hp? 30 gallon? 50 gallon?

It's actually Dad's ... and he never took care of it after owning it for 15+ years. We have a few air tools (largely unused) but mostly it's used to inflate tires and occasionally clean things like dandelion fuzzies out of our tractor's radiator.

So, it's only run a few minutes at a time once each week.

Anyway, I checked the oil this past summer and it looked nearly black. With no byproducts of combustion to deal with, I felt that this was definitely NOT GOOD.

Also, it was at least a little low. Evidently, no one had even checked the oil level for the past decade.

I drained it, refilled it with some leftover (new) ATF and then ran it for 1 minute. Yes, I heard it knock a bit with the thin ATF in there but I was just cleaning it out. I drained the ATF (a long time, with the machine tilted) and filled the crankcase with NAPA's compressor oil. It wasn't cheap (about $5 per quart) but it only took 1/2 of the bottle so I can change the oil again in another year or so.

--- Bror Jace

 

[2K2AcuraTL]

It would apear that draining that M1 15w50 would be a good idea.....

I will look for this 20 or 30 wt oil.
Thanks
Jean

 

[Bror Jace]

There was another topic here which centered on home compressor oil. But the forum has been reorganized several times since then ... perhaps it's in the "Heavy Duty & Industrial" section?

--- Bror Jace

 

[Jimbo]

I have a twenty year old Sears cast iron air compressor and switched to SAE 30 when 20 became unavailable. I change it every other year or so. It still runs strong with no unusual noises. I don't think a multi-grade is a good idea in these units, as they are splash, not pump lubricated.

 

[Bror Jace]

Jimbo, in these parts, using a straight weight oil can be a problem come wintertime.

I knew a guy who put a straight weight in a compressor (30? 40? 50?) stored in an unheated garage. When he tried to get some air out of it in the dead of winter, it would make about 2 flops per second. He didn't care about it and plugged it just so we could all have a few laughs.

Dude wasn't the sharpest bulb in the chandelier.

--- Bror Jace

 

[Jimbo]

Good point. The manufacturers must assume that the equipment will be operated in a heated workshop in the winter.

 

[Tommy]

Amsoil has synthetic compressor oil available (quarts) in SAE 20 and SAE 40. I am going to run their SAE 40 in our shop compressor. (heated shop)

 

[RB Shannon]

I'm running Amsoil's 20w compressor oil in an ancient Craftsman,and it ran very well in an outside shop last winter.