rust in air compressor

[taem]

Just bought a used 60 gal air compressor 5 hp motor, in reasonable shape. there is some rust in the water drained from the tank. I plan to plumb it in my shop and am cleaning it up now. I know I will need to drain it after each use, but does it make sense to try to rust proof the inside of the tank before setting it up? Over the years, the thing that killed my compressors has been tank rust out and I want to avoid it. It occurs to me that I could pressure wash it out via a 1 1/2 bung on the side, dry with warm air, treat with POR etching primer and spray a finish coat of POR rust preventer in, again letting it dry for a logn time and then plumbing it in. So, questions: is it worth doing at all? any downside other than cost and time to this plan? any better suggestions?

 

[Patsdeere]

I would think an auto drain would be the best. Still going to be moisture in the air, but as it cools it will drain, but never sit. Maybe a longer tube out of the drain to prevent any moisture from sitting in tank. I guess I'm lucky living in a relatively dry climate.

 

[Steve@Advance]

I've never tried to rust proof one. My concern would be when it starts flaking off it's going to clog the drain.

I would invest in an automatic timed drain valve. Start with an easily accessible ball valve, then a fine screen Y strainer, then the auto drain. Set the timer for several short drains throughout the day, that way it stays mostly dry in the tank.

 

[Stephen Newell]

Perhaps if it was an unused tank that might be a good idea but on a new one you would never get it cleaned well enough for anything to adhere. If I was going to put anything in a tank it would be a fuel tank liner. It's rubberized so if it failed it might come loose in a whole sheet but not in bits and pieces.

The tanks should be sealed at the factory when they make them but I don't think they do that anymore. I bought a new campbell hausfeld compressor and it's had a sea of rust coming out of the tank from day one.

 

[Loosehandle]

Dry it out and coat inside with oil

 

[showcrop]

When you say "drain after each use" do you mean that you let all the air out at the end of each day?

 

[kris Jensen]

As long as you hav water in it for more than a day it will be rusty. It id the law of nature.
I had a pancake compressor i.e. small tank. with lots of rust which was my fault. I cleaned with a
pressure washer, then put in a solution of rust remover. industrial vinegar I think (11%). then I let it dry in a warm sunny location on the driveway
Final touch was to slash around some diesel fuel to coat tank. whatever, it worked and I learned to dry tank often
You had some suggestions as to auto systems that should be really good.
A little bit of oil will not hurt your air tools, just don't try to paint before you have it really dry.

 

[JD Dave]

X2 auto drain. You can waste a lot of time trying fix the rust inside to no avail. Put it in service with an auto-drain timed frequently and the inside will be dry in 5 days. Sooner when there is lower humidity.

 

[glennster]

if you ever plan on using the compressor for spray painting, never put oil or diesel or anything in the tank. the paint will fisheye like crazy. for an inexpensive drain, use a small petcock in the bottom of the tank and leave it cracked open just a hair so it barely hissed. it will drain by itself.

 

[rustred]

that is why u blow down the compressor each day. there should be a valve at the bottom of the tank. i always blew it down each morning at work before turning it on. always lots of water would come out. nobody ever blows down a compressor at the end of the day from what i have seen. to much in a hurry to get home. but thats probably the proper way blow it down and let it sit till morning with no air.

 

[Stephen Newell]

Funny, I worked for a customer onetime fixing things at his house which was over his head. He did the things he could do and at the end of the day he let all the air out of his compressor with his air hose. After a week of seeing that I had to ask and he told me the directions said to do that. I had to show him where the drain cock was and he drained it there and I bet the thing was half full of water.

 

[taem]

Not all the air, just the water from the petcock at the bottom.

 

[rustred]

and another thing u can do is add air brake antifreeze to the system before turning it on each day. we always did that on the oil rigs to prevent air lines freezing. the thing is people take too much for granted and dont properly do their preventative maintenance.

 

[Geo-TH,In]

I have 3 air compressor tanks I found along the road. The compressors go bad before the tank rusts out.

I have a very old 1.5 hp twin stage air compressor. The tank is still good.

The last roadkill tank is a 20 gallon tank Campbell Hausfeld. I plan to use the tank as a portable air tank.

Tubeless tires are like air tanks. The rims can rust out too. Some tire shops are now using Nitrogen instead of compressed air.

 

[Stephen Newell]

That's why I had to but in, this guy was letting the air out instead of the water.

 

[504]

Auto drain sells for less than 20.00 at Harbor freight but you must have a sensor line . They are easy to install just read the instructions in the box before buying or check on Utube