Sullair blowing oil

[barklee]

I have a 1996 Sullair 185 DPQ compressor that is having issues. We have been using it to sandblast with and it has been blowing oil into the moisture separator on the blast pot. Also it is blowing oil out of what i assume is some sort of bypasses, one is right above the compressor head on the left side and another near the back of the control panel. It has been cold so i was thinking maybe something is freezing but we have kept the hoods closed and it seems that everything is warn inside the machine. Also, we went to top off the compressor oil shortly after shutting down and there was a bit of pressure behind the oil filler plug. It will slowly overflow when removing the cap. Any ideas??

 

[VoodooMojo]

usually its the oil separator in the receiver being saturated or in need of replacing that causes this.
Dont run it that way for long or you will soon see an extremely large fire erupt.

Rotary Screw Compressors need a rather large supply of oil to keep the screws from turning bright red from friction heat.
The separator is a large filter element that removes the oil from the output air that wasn't knocked free from the air when it rammed into the side of the receiver.
The oil coming from the other components (pressure regulator and unloader valve) is a sure sign that the oil is still suspended in the air and not falling to the bottom of the inside of the receiver.

edit:
there should be a sight-glass that will let you know if the oil level is too high or too low. The top of the oil level should be visible in the sight-glass and not over filled.
You may just be over filling the oil tank (receiver).

 

[barklee]

usually its the oil separator in the receiver being saturated or in need of replacing that causes this.
Dont run it that way for long or you will soon see an extremely large fire erupt.

Rotary Screw Compressors need a rather large supply of oil to keep the screws from turning bright red from friction heat.
The separator is a large filter element that removes the oil from the output air that wasn't knocked free from the air when it rammed into the side of the receiver.
The oil coming from the other components (pressure regulator and unloader valve) is a sure sign that the oil is still suspended in the air and not falling to the bottom of the inside of the receiver.

edit:
there should be a sight-glass that will let you know if the oil level is too high or too low. The top of the oil level should be visible in the sight-glass and not over filled.
You may just be over filling the oil tank (receiver).

View attachment 127301

That makes sense. Do you have a parts book or have the filter part number? I actually changed the hydraulic oil a few weeks ago and filled to the center of the sight glass. At that time i replaced the screw on filter thats mounted on the A frame. Didnt realize there was a filter in that tank...... Thanks!

 

[kshansen]

Hopefully VoodooMojo can give you the numbers.

One thing I seem to recall when I went to a Sullair class was the oil separators come with gaskets that have staples in them. Was told DO NOT remove the staples. They are there to help ground the cover to the filter and to the tank. If they are not there I was told static electric charge can build up and cause an explosion. Maybe VoodooMojo came confirm this?

 

[Moonlite]

Kshansen is correct DO Not remove staples. I have seen one that caught fire from static elect build up. It was a mess to clean up.

 

[barklee]

Kshansen is correct DO Not remove staples. I have seen one that caught fire from static elect build up. It was a mess to clean up.

I took the old filter out and noticed it says not to remove the staples.
The filter doesn't really look too bad to me. Would there be anything else that would make this blow oil besides this? The part number was also stamped on the filter so I should be good to go there.
Thanks

 

[Moonlite]

Im sure there are other things that could cause this. I just havent seen anything cause it other than the seperator.

 

[Moonlite]

Be sure and check the scavage tube for trash.

 

[willie59]

The staples in the oil separator filter element ground (earth) the element. The top cover completes a ground to the receiver tank via the bolts that mount the cover to the tank. The element, however, is electrically insulated to ground by the gaskets for the element, hence the reason for the staples, to provide a ground for the element.

 

[VoodooMojo]

if the minimum pressure valve is leaking you will more than likely have this issue but it is rare. If it is the problem it can usually be repaired by replacing the seals on the valve. Any Sullair distributor can get you the valve or the seals.
But it is rarely the valve.
This valve is mounted on the top of the receiver tank.
Disable the engine from starting (fuel shut-off valve if diesel or coil wire if gas) but still be able to crank the starter.
Open the output air service valve and crank the engine over. If air is coming out the air valve while the engine is just cranking then the valve is suspect.

The filter separator element will seldom look like it needs replacing but it is normally what is causing the issue.

Also, the correct oil is important. Does it blow oil immediately or after it gets good and hot? If it starts after getting hot it usually is the oil. Many revert to ATF when in doubt.

If the air coming out of the service valve is hot it may well be as Moonlite pointed out, the pick-up tube from the receiver to the cooler may be restricted and not permitting proper lubrication to the rotary screws. This is usually safety checked by temperature shut down switches located near the rotary screw and the receiver tank. These switches have been known to be bypassed by some jamoke thinking they know what they are doing.

I can relate a real ugly story about what happened at a vacuum cleaner manufacturing plant in Bloomington Il. when someone did this once. Let's just say it made the evening news.

 

[Paul Six]

If you are shotblasting make sure that the diameter of the pipe at the end of your blasting hose is 8 millimeters or less , for 185 CFM 8 millimeters is a max , 6 millimeters is fine , if you work over the capaccity of the machine the seperator don't last long

 

[barklee]

if the minimum pressure valve is leaking you will more than likely have this issue but it is rare. If it is the problem it can usually be repaired by replacing the seals on the valve. Any Sullair distributor can get you the valve or the seals.
But it is rarely the valve.
This valve is mounted on the top of the receiver tank.
Disable the engine from starting (fuel shut-off valve if diesel or coil wire if gas) but still be able to crank the starter.
Open the output air service valve and crank the engine over. If air is coming out the air valve while the engine is just cranking then the valve is suspect.

The filter separator element will seldom look like it needs replacing but it is normally what is causing the issue.

Also, the correct oil is important. Does it blow oil immediately or after it gets good and hot? If it starts after getting hot it usually is the oil. Many revert to ATF when in doubt.

If the air coming out of the service valve is hot it may well be as Moonlite pointed out, the pick-up tube from the receiver to the cooler may be restricted and not permitting proper lubrication to the rotary screws. This is usually safety checked by temperature shut down switches located near the rotary screw and the receiver tank. These switches have been known to be bypassed by some jamoke thinking they know what they are doing.

I can relate a real ugly story about what happened at a vacuum cleaner manufacturing plant in Bloomington Il. when someone did this once. Let's just say it made the evening news.

Is the receiver tank what the separator element is housed in? If so there is a valve on the side which i presume is a pressure relief? That is not what was bypassing, it was the two inline hoses (guessing 1/4" hose) that come off this tank that houses the filter element.
I called the local Sullair dealer before we changed the oil and we use 32 hydro oil based on what they said. This problem was happening before this however. Thanks

 

[JRIC61]

simular compressor problem

I have basicly the same problem with an old leroi compressor q185 model,also blowing oil out thru the intake of compressor,all stared with speed control cable snapping,which works off an intake valve,pulls the throttle down when set pressure is reached and pushes it back to rev engine when pressure drops,,i noticed the oil very low,so we filled it with hydraulic oil.since then it spits out all the oil wont stay running stalls and smokes alot thru intake,can keep it running by holding bypass button,but im sure thats not to safe at all,oil is very hot when ejected so im sure its not circulating thru the cooler,takes mere seconds to get very hot. notice a valve oon a line coming out of resivoir called a dump valve supposed to blow down any residual air pressure left behind.but like i said it blows out intake instead,noticed some one said oil type very important,and something about using atf to be safe,any advise on that,could it be the oil causing the heat causing it to boil and erupt?this is my first post,i hope im doing right by asking for help here. thanks

 

[VoodooMojo]

If air is blowing out of the air intake then the issue is more than likely in the check valve at the discharge end of the rotary screw. The check valve is used just for that purpose. They get hot as hell when the oil gets low and have been know to melt, stick in an open position or even catch on fire.

Where the big tube from the receiver to the air-end attaches to the air-end or at the receiver there will be a removable housing containing the check valve.

I do not recollect ever working on a Leroi but the valve will have to be there or compressed air in the system would just rush straight back through the system and out the air cleaners.

Some are poppet looking things and some actually look like an oversized ping-pong ball.

 

[VoodooMojo]

Is this the Leroi?

 

[JRIC61]

This pic is is very simular to it,probably a close mode lof one,mine has a lil different configuration of intake setup,my question (first of all thank you for the reply)my question would now be is this valve you refer to one of the valves coming from a line attached to the resivoir,there is the blow down dump valve,and another which is a fillter type valve that lets oil return ,but its tiny like 1/4 inch ccopper ,and one other line that is the control valve,used to set pressure amount.
or is it on or in the large hose coming from the resevoir?should I take the cover off the resevoir,and inspect the element in it

 

[JRIC61]

That is very simular to mine,mine has a lil dfiferent intake setup.is the check valve your refering to one of the valves seen on top of resivoir,one is called a blow down dump valve,the other is a filter and drain for excess oil.or is there another in the hose your speaking of,and is the reason maybe i used hydraulic oil instead of compressor oil. causing the blow back.thanks for replying earlier,I certainly appreciate it

 

[VoodooMojo]

the hose and valve I speak of is the large (probably braided) hose that runs from the bottom rear of the air-end (compressor screw) to the receiver. The check valve will be at one end or the other of the hose.

I was looking for an image of it on the web last night but, alas and alak, I found none.
If you can post photos of the area we can hone in on it.

 

[VoodooMojo]

the separator element in the receiver will not be your issue...that can only cause oil coming out the air discharge end.

The more I think about these rotary screw machines the more i remember my days on Sullair, Worthington, Garner Denver, Joy, Sullivan etc compressors.
The valve I speak of is many times installed right in the fitting at the air discharge end of the rotary screw

 

[FSERVICE]

The more I think about these rotary screw machines the more i remember my days on Sullair, Worthington, Garner Denver, Joy, Sullivan etc compressors.

then I want a drink to forget bout it!!! LOL