I painted a bedside a few days ago and the paint was full of "fisheyes". After hunting for an answer, I found out the check valve in the air transfer tube was stuck open and causing oil to blow into the air tank from the air pump. I fixed the valve, but what can I do now to prevent any more oil from contaminating my paint jobs? Can the tank be cleaned out? Is there any kind of industrial strength filters that would stop the oil from reaching the paint gun? I really need help on this, so any advice would be greatly appreciated. By the way, I wasn't using any kind of filter on my compressor before, just an air hose straight from the compressor to the gun. I don't paint that often and thought I wouldn't need one. Before the vale stuck open and blew oil in the tank, I never had any problems with contamination in the paint. Again, all suggestions would be greatly appreciated. Thanks in advance.
03-20-2010 12:03 PM
Oil in air?
Hi, the check valve sticking should not cause oil to get into the air. Oil blowing by the rings may cause that. Are you sure it wasn't water. A water filter is essential for any compressor when spraying paint of any kind. You should be able to drain the tank which you should do often anyway.
03-20-2010 07:24 PM
I try and drain the tank every time I use it, but it could very well be water getting in the hose. I don't know much about it. Just thought it was weird that I was getting good paint jobs for a couple months. Then, after the valve stuck, I wasnt able to paint anything without getting nasty fisheyes. Do you know of any good filters I can put on the compressor to eliminate any contmination coming from the compressor tank, water or oil? Thanks.
03-21-2010 09:00 AM
If oil was going by a valve that was stuck open then it would just as easily pass through one that is working normally, fixing it would make no difference at all. Fixing the stuck valve is important however because it causes a huge overload on the motor at start up if it is stuck open, BTW how did you determine it was actually stuck?
Running a hose straight off the compressor is just begging for trouble and with no filter/separator I honestly don't see how you ever managed to get any paint to go on without major problems! Washing out the tank is not the solution to your problem, do a search here on air systems and invest in some piping and a good filter/moisture/oil separator. The pipe system and filter/separator are a necessary part of the overall air system and they are NOT optional, simply draining the tank is not going to do much good at all if you don't have a complete system!
J. E. Allison
03-21-2010 06:40 PM
I live in a humid location, and condensation in my compressor is a major problem, I don't paint with it but I hate water in my tank cause its bad for the compressor tank, and I don't like the combo air and water coming out the end of my hose.
I have an up-right tank with at drain valve at the bottom. That little piece of sh-- (POS) valve was always sticking and if It did open, it would not let the crap out and would plug up. So I bought a 90 degree fitting and a brass nipple long enough to bring the valve to the side of the tank, it is still the lowest part of the tank, I bought a small ball valve to use as a drain valve. It works like a charm. When I'm using the compressor a lot, I just crack that valve just a little and leave it cracked to let the condensation out.
I'm not a big fan of harbor freight, but I saw what looked like a good water and oil separator for compressors over there. Its worth a look! But I cant see why you have oil problems with your compressor unless you have just worn it out!
Here is a link from across the pond that might help you!
03-22-2010 07:58 AM
That old red's pretty smart.....after you get the filters dont forget to get a new hose....use the old one for anything that isnt sprayed...it's contaminated
03-22-2010 09:23 AM
Thanks for the responses, guys. I'm definitely going to get some good piping and filters this week. I most have just been lucky with the earlier paint jobs, I guess. There is a little vent on top of the compressor pump that was producing a fine spray of mist. When I called the company 800 number, the guy on the other end told me the mist was oil and it was caused from the check-valve being stuck open, which, in turn was blowing air pressure back into the pump. I just assumed that the oil was getting into the tank from the pump, but water does sound like the logical explanation. Thanks again.
03-22-2010 10:52 AM
You'll crap yourself when you find out what they cost....if your handy and can weld you can make them fairly easily.....also get a small filter for your gun they run about 5.00
03-22-2010 07:19 PM
Deadbodyman,Im A decent welder. Do you have site I could go to that would kinda tell me what I need and how to get started? And what is your opinion on the filters at Harbor Freight? Would they work for what I do? I only paint about once or twice a month. Where do you find the small filters for your gun?
03-23-2010 05:05 AM
I think I saw those gun filters at HF but I get mine at my paint store...Sorry guy no web site I just learned how to use a computer last year,thats way over my head.Someone was telling me HF had some pretty good water filters.but I cant say for sure....I'll start a thread on making some since I'm making some for my woodshop....They're surprisingly easy