Compressor Maint

[cstreit]

Gang,

My compressor states that I must drain it after every use... Is this really necessary?

I know some water will build up, but shouldn't it be lined with something to prevent rust? Even the first time I got some water out of it, it was a bit brown and oily, should I be worried?

[5axis]

The first concern is that the oily brown gunk is making it's way into your air tools. A inline water separator and oiler do wonders for pneumatics.
Weekly or monthly draining might be fine. It kind of depends on your usage and the moisture going into the system. Sticky 90-90 Illinois day and you will accumulate lots of water. Bring on the 90's anyway.
david 89 turbo cab

[MotoSook]

Chris, drain the tank often is my advice. I put an old rag under the drain valve after I clean up the garage post surgery and let any moisture drain/blow ontot he rag. No mess on the floor.

As axis said, in the summer, it matter most. I have gotten probably 1/2 cup-1 cup of water out after a long day in the garage with the compressor going on and off all day.

When they manufacturere the tank, they may have swabbed the inside with oil to prevent corrosion until it hits the customer. So that oily brown stuff is likely a combination of oil and rusty water.

[cab83_750]

This must be a bad and perfect timing. I just bought Sears big-Mama 220 v compressor.

The drain is a PITA to open. However, few days back, I encountered a unit that is supposed to drain the tank AUTOMATICALLY. Now, if only I can remember where I saw that unit!

Maybe others can chime in.

[cstreit]

Cab, really?

If you find this unit, could you post it?

Is it necessary to drain ALL the air, or just untill most of the moisture comes out?

[MotoSook]

Chris, the little valve on the botyom seals pretty well with litte torque on it, and I only crack it until I can feel only air coming out. If you are not confortable after that, you may just come back later and do it again, giving any condesation time to run down to the bottom of the tank.

For a cheap and simple solution, if you don't want to get on your knees to drain it, plumb some 1/4 (you can get high pressure tubing at easily) stainless tubing to the bottom and run it up to a comfortable level. Use a valve at the end of the tubing and aim it down. The tubing should be bent like the p-tube under you household sink. The air will force the water out and into a cup or bucket under the valve (think coke bottle or beer bottle when you shake it and turn it upside down then release your thumb)). If you look under the tank you'll see it is just a valve screwed into NPT threads (I think NPT).

I'd be interested in seeing an auto drain...more like I'd be interested to pick it apart. For such a small system, this is unnecessary. I use the above drip drain on large piping headers to prevent corrosion in high pressure manifolds/headers and my customers love it.

[cstreit]

You know if you hooked a drain tube up to then end, and them expanded it via larger brass fittings, most of the condensation would drain to it even before you drained the tank. It would run into this tube and not sit in the tank even for a little while... Hmm... I sense a run to ACe...

[HawgRyder]

You might want to look into the drain valve used on truck air systems.
It's automatic...and needs almost no maintenance.
You would need to put a line on it to direct the water outside...or down a drain....but it will keep the air a lot drier.
Bob

[cstreit]

Howzit work?

[rfix'n]

Harbor Freight sells the auto drain assembly. Have not used or seen it in person, just in their catalog that seems to come to my mailbox on a daily basis!

My compressor is only two years old and I've had to replace the drain valve as it would not seal properly without using a pliers. Now I just throw a paper towel under there, drain for a couple seconds, finger tighten drain valve.

[MBAtarga]

I have no connection, but the guy on this site provides a writeup on how he used this $10 Kit.

Edit: I was getting all fancy, smancy with neat links in my post, and Rob beat me to the answer!

[MotoSook]

If you tighten that drain valve with gorrila strength, it will compress the seat too much. Us as much strength as you need to in order for the valve to seal, and it will last a lot longer. It is an easy valve to replace.

[cstreit]

Good reference Mark, thanks!

[widebody911]

At the local Air Tool Store (that's actually what it's called) they have a special timer valve setup which will open the drain for a given length of time once a day.

I snapped the handle off the valve on mine; it's been a while since I drained it.

I bought my compressor used, and one of the first things I did after getting it all hooked up was to drain it. There must have been 5 gallons of water in that thing, made a huge rusty brown mess all over my garage floor.

[rhaas]

The way I deal with it is to leave the drain cracked and slightly leaking air. Put a cup under the drain and it will drain automatically!!!

[john70t]

You can also try blowing air through the motor while it's running to get the dust out of the brushes.