Compressor Oil

I have a small compressor which states on the machine, SB 420 oil only. I cant seem to find the oil on the internet, any other type of oil suitable.

Bob.

Obsolete according to this:

**LINK**

Not sure what you call small but any light compressor oil might do. Anything special about this compressor? Usual buzz box 2800rpm? Aluminium or cast iton? Single or two stage?

Maybe something like this will do it Bob.

**LINK**

Toolstation and Machinemart all sell compressor oil.....

Edited By John Rudd on 17/04/2018 17:10:35

Some interesting background to the SB classification here **LINK** and here **LINK** .

Essentially its an older relatively low additive oil formulated for engines that spend significant periods stopped and have widely varying load / speed ranges. So it has a decent amount of anti-corrosion and anti-condensation properties. For all practical purposes anything up to, but not including, SM works just fine on older automotive engines made when earlier designations were current.

420 is the viscosity. presumably in Saybolt SUS rating at 100°F as nothing else I've found makes anything approaching sense. Straight SAE 30 covers about 380 to 600 SUS at 100°F so presumably would be a modern equivalent. Basic hydraulic oils are popular for this sort of relatively undemanding application but do make sure you have decent amounts of anti-corrosion and anti-condensation in the specification. If going the hydraulic oil route note that ISO grades are specified at 40 °C so are closely comparable to SUS at 100°F although the numbering is quite different.

One thing to be careful about compressor oils is "off-duty" cycle. Many compressor oils are formulated for industrial devices that run most of the time. Some oils can be unhappy if left to stand for long periods. The special oils for Hydrovane compressors are a case in point where its important that the beast be got up to temperature when run so as to drive out any condensation.

Personally I just shoved a decent brand SAE 30 automotive oil in my Atlas Copco KE 2 with an oil change when I thought about it, probably every 3 or 4 years. The Atlas wasn't new when I got it 40 odd years ago but its been going fine on that sort of service regime ever since. I've sold it 4 times and taken it back 3 times so far when the current owner decided to copy me and go Hydrovane for peace and quiet in the shop. Perhaps I'll look at the valves next time it comes back. Or perhaps not!

Clive.

SAE 30 is what the manufacturer ot my compressor ( pilot ) recommends and it is what is generally used in small engines like lawnmowers so if you only need a small quantity try a mower shop or some auto shops sell it as well, i get mine from supercheap auto here in OZ and its labled as small engine oil .

Thanks for all these informative replies.

Bob.

When I was in work, years ago, our Shell rep kindly got me 3 or 4 litres of Coprena P150 for my small direct drive compressor. This, or its successor may well be available fairly easily.

Howard

I just use 5w-40 synthetic engine oil........never a problem in god knows how many years........

My main compressor (I have 4) is a huge, direct drive Ingersol Rand V twin, 3 phase .......would cost about 2 grand to replace and I use the synthetic in that as well......changed 1'nce per year........never a problem......

clogs

,

My wife's car, a Corsa 2009 uses 5w-30, and states on a service 20.000 miles per oil change. If its good enough for that after 120.000 miles then with replies on oil I shall bung 5w-30 in .

Again thanks for replies, Bob.

Edited By BOB BLACKSHAW on 19/04/2018 21:06:56

Bob,

As an engineer, retired after a lifetime in engine manufacture, development and use, I would not run my car beyond 10,000 miles between oil changes, even with modern synthetic oils. Honest John in the Daily Telegraph supplements, is of the same mind, and he (they),have experience from many marques and models.

I've seen the results of "saving" on oil, cost a lot more in wear on other components!

Howard