Compressor question

I have a Husky upright, not the great big one, but the one about chest high. Two cyl compressor. I bled the tank today, and got water and a white milky oily fluid. Checked the dipstick, and it is low. I'll get some Husky oil today and fill. Do you think I damaged the compressor? Is the white oil in the tank normal?

TIA

Steve

Reply to
Steve B
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Yes it is normal, and no you probably didn't hurt the compressor unless the oil level had dropped below the oil slinger on the bottom of the connecting rod cap.

Also, there's nothing special about compressor oil--the overwhelming majority will be perfectly happy with straight 30 wt non-detergent just like is used in lawnmowers etc, just don't use the wrong weight ( or a multi viscosity oil ) because the oil distribution system is based upon known oil properties as well as crankshaft speed.

That white liquid is condensate mixed with a small amount of oil, the amount generated will depend on total compressor run time and outside humidity.

Actual oil consumption is dependant solely upon run time ( discounting worn out piston rings ).....What this means is you might go several months without having to add oil as long as usage is light....

--but if all a sudden you spend an entire day constantly using an air die grinder or some such then you can almost bet that the oil needs topped off.

By the way, if it has a cast iron pump unit then it is most likely the same one that's used on compressors offered by a very large number of different "manufacturers"

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Reply to
PrecisionmachinisT

...My big 3-phase monster takes Mobil-1 10W-30 Synthetic. Which Dayton charges $29 per quart for or something like that.

You can't imagine how pissed off I was when the UPS package showed up with my compressor oil and it was Mobil-1 off the shelf of the auto parts store at that price...

Reply to
Joe AutoDrill

Ouch. Mobil-1 is definitely good oil though, I use it in most everything.

Reply to
Pete C.

I've heard compressor-oil is low-ash and - well, something to do with compressors have a high "compression ratio" and can make a mess of ordinary engine oil - or even run as a diesel engine combusting the wrong crankcase oil.

Reply to
Richard Smith

I dunno about that , but I've seen piston rings that were so carboned up that they couldn't seal properly . That was in a pump that as run way harder than the rated duty cycle though .

Reply to
Snag

It could have been Mobil-1 off the shelf oil in a fancy-pants compressor-oil packaging, so that you would be coming back for more quarts at $29 a throw. Be thankful for small mercies. ____________________________________________________________________ Gardner Buchanan gbuchana(a)teksavvy(dot)com FreeBSD: Where you want to go. Today.

Reply to
Gardner

It will clog air valves on your cnc equipment especially mac and festo.

Reply to
PrecisionmachinisT

The current diesel rated oils are "low ash" as a result of diesel particulate filters on current emissions controlled diesels. I use Mobil-1 5W40TD in my diesel truck and also in my diesel tractor.

Reply to
Pete C.

Chapter two: I went to the borg and bought a pint or so of compressor oil for $250 US. Came home and found out that my compressor crankcase had just as much oil in it as it needed. It was not black, but not clear or white as I expected from the white oily stuff that came out of the bottom of the bleeder. I didn't open the bottle at all, so am not sure what color the new oil is. BUT, now I am curious as to what the white oil was in the tank with the water? Anti rust stuff? The compressor works fine, pressures up fast.

So, back to trying to identify the white oily liquid. The compressor is just as it should be oil wise in the crankcase.

One last question: When checking oil, is it proper to stick the stick the

3/4" or so down into the casting, or check the level by just putting it in until the stick hits the casting? The bottom of the dipstick has a bell shaped plastic area. You then have to push it into the casting to get it all the way in. I know in cars and lots of machinery,you stick the oil stick in all the way, but have wondered about those others with screw in dipsticks, or these push in types. Which way is correct?

Steve

Reply to
Steve B

LOL

Right wingers and their killfiles.....

Reply to
PrecisionmachinisT

While we're on compressors...

Anybody have any info on thie compressor?

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Dunno how old it is. Seems to work well except for an annoying problem described on the web page above.

Atlas-Copco seems to have no record of ever having made/sold it.

BTW,when it's been running, the oil in the crankcase is milky, I assume from getting water homogenized with the oil. Using 30 wt. non-detergent motor oil. Should I be using something else?

It's rated for 400+ PSI but I only run my tank up to 150 PSI so the compressor is presumably more or less loafing.

Reply to
Mike Spencer

Suggestion / question - is the white at-least partly oily stuff a suspension of oil-in-water (like milk itself) or vice-versa (water in oil)?

A rough experiment would be to heat up some of it - water would steam off and you'd be left with clear oil (OK - sorry - some of us have this problem that we always try to jump to a way of finding-out these things... :-) )

Rich S

Reply to
Richard Smith

Very good point.

Reply to
Joe AutoDrill

Wow, that's expensive! I could have made a truck payment with that. (Didja forget the decimal point? ;)

I change (or try to) my compressor oil annually. Isn't it time for yours?

I always put it all the way in and screw it down if it's normally fixed that way. Whatever way you choose to do it, always check and fill it the same way. Then you'll be assured that it always has the proper amount of oil in it.

-- In the depth of winter, I finally learned that within me there lay an invincible summer. -- Albert Camus

Reply to
Larry Jaques

I would guess non-compressibles in the high pressure section are being vented off...

--definately beats the alternative.

Maybe it's never getting up to the proper operating temp.

Reply to
PrecisionmachinisT

Duh. Makes perfect sense. The right amount of oil or oil/water emulsion would do it, wouldn't it? It's an old beast, probably heavily used for many years. And oil mist does blow out when the valve pops.

But it never occurred to me that the amount of oil reaching that stage could make that difference.

Yeah. Oh, yeah.

Thanks,

Reply to
Mike Spencer

If you don't want to grovel in the presence of your machines you can connect a hose to the bottom fitting and raise the drain valve to a more dignified location.

jsw

Reply to
Jim Wilkins

I replaced the drain valve with an elbow and a short length of hose.

Occasionally, I press the button on the attached blowoff nozzle to drain the tank. Cheap and fast.

Clears the driveway of cats.

What's not to like?

--Winston

Reply to
Winston

Cats ?

Reply to
PrecisionmachinisT

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