This is Fine, Right? (Air Compressor Content Inside)

My father downsized to a senior condo this summer.  This is one of my new toys:

He bought it new.  I think it's about 25-30 years old.  It received light residential use.  Works perfectly.  Never loses pressure. This would be a nice upgrade over my NOISY oil less Craftsman compressor, which is also almost 25 years old.   This one has a better motor, better compressor, and a bigger tank. 

Did you notice that orange puddle behind the compressor?  Of course you did, it's huge.  I guestimate that about 2 cups of water came out when I opened the drain.  Is it time for a new tank? Is this thing a bomb about to go off, or is it an oil change away from another 30 years of reliable, boring homeowner service ? 

I drain mine after each use and leave valve open attempting to avoid that. Is it possible to get a scope thru an opening to inspect inside?

It won't explode, it will eventually start leaking from pinholes in the bottom.  If you are nervous, turn it over and beat on the bottom of the tank and see whether it collapses.

Did any particles or chunks of rust come out the drain? 

That is probably typical of light residential use. 

Tanks will collect condensation w/o use just from the heat/cool of ambient temps in storage. 

Like outasite said, try to get a scope in it. Other than that change the oil and inlet filter and run it. 

I drained a tank at my old job that was big enough for me to climb inside of and ran at multiple hundred of PSI. I don't know how much water came out because it just went down the drain but I was shocked. Never had a problem. You should be fine. 
Also we installed an auto drain after that. 

You're fine.  Its a common problem for people to have with their compressors. They run em and when done they forget to drain them.  If it were a gallon or more rmthat came out I'd be concerned.

I'd make it a habit that when you are done with it you open that drain to let the pressure out.  

outasite said:

I drain mine after each use and leave valve open attempting to avoid that. Is it possible to get a scope thru an opening to inspect inside?

It hadn't occurred to me to leave the valve open. Makes sense.

Anyone else do this?

In reply to Floating Doc (Forum Supporter) :

I've done it that way for years figuring it wouldn't hurt. 

That's normal.  Don't sweat it.

I always leave the valve open and leave it open for about 10 seconds when I start it. It blows out a lot of moisture.

Trying to find a way to scope it , although a good caution, would be WAY overkill for this. That's actually quite clean for the circumstances., Entirely normal. Also, as mentioned, it will not rip open catastrophically, unless it somehow builds pressure into the 4 digit pressures! Even then, prolly just leak through pinholes (albeit larger holes!)

Give it some fresh oil and enjoy.

It should be fine.  When you close the valve, don't cinch it tight.  I leave mine ever so slightly leaky.  It makes an almost inaudible hiss.  It doesn't hinder performance, but if I fully charge the tank, it might take a couple days to drain to zero pressure.

But it always drains.  I never have to open it to get water out.

I have never drained my compressor, tried once, the valve is broke.

At work we have had a couple of compressors rust through, they just leak progressively worse until we weld or scrap them.

I have seen an industrial compressor tank burst due to rust, but that was in Miami where a combination of extreme humidity and lack of maintenance led to the explosion.  Guy lost his hand.

My last compressor was never drained on a regular basis. It was years between drains. Chunks came out when I finally did.





The chunks just below the tank in the first pic were coaxed out with a screwdriver. It worked fine after the drain for a few months, but the regulator quit, so I used that as an excuse to buy a bigger one.

My new compressor pretty much gets drained after every use.

Once they have a couple of pinholes, they're self-draining.  

I used to drain a ton of water out of mine after a day of use, it's humid in south florida- looks fine to me.  

Mr_Asa said:

I'd make it a habit that when you are done with it you open that drain to let the pressure out.  

If it is a plug, wait until the tank has no pressure.  I made the mistake of unscrewing the plug while there was still some pressure in the tank and not only am I lucky I found the plug, I'm lucky I still have all of my fingers and that I didn't have a beautifully painted floor.  
 

Thanks everyone.  

Given the responses, I'll run it as is. 

I changed the oil, and used the bottle of compressor oil that came with the compressor.  It was purchased from Montgomery Ward for $1.39.  There was a number on the bottle that looked like a date code.  June something, 1992.  So,  this was probably its first oil change.  The old oil looked sort of graphite colored, but without glittery solids. 

One of the pressure gauges is frozen in place at 90 psi, probably from sitting right there for 20+ years.  I ordered a new one. 

The drain is a petcock. Of course, the little end piece that you twist worked loose, so I removed it completely. I'm thinking about plumbing a hard line out to the edge of the tank so that I can see it, which will remind me to drain the water now and then.  I think I can just put a air nozzle on the end so that I don't have to unscrew anything.  Or maybe some kind of quarter-turn valve that maintains a seal at 125 psi.  

In reply to Uncle David (Forum Supporter) :

I used a quarter turn ball valve on mine.

There was sediment blocking the drain hole, so I unscrewed it, and it turned out to be 1/4-20 or whatever the quarter inch brass equivalent of that is. Elbow, nipple, ball valve, tank drains much happier and quicker now, and it's MUCH easier to reach than some little dial 6 inches away from the edge of the tank. 

Leave the valve open when not in use and let it run for 30 second or so before I close the valve every time too, it's amazing to me how much moisture build up there is with it just sitting in the garage. 

Another mod I recommend is mounting the compressor on an HF furniture dolly. Makes moving it around so much easier. 

maj75 (Forum Supporter) said:

I have seen an industrial compressor tank burst due to rust, but that was in Miami where a combination of extreme humidity and lack of maintenance led to the explosion.  Guy lost his hand.

Sorry somebody lost a hand do to poor safety. But there was more than just rust from excessive buildup of condensation. True its worse in the extreme humidity. But condensation causes rust. Rust in a (reasonably) low pressure vessel causes pinholes. Pinholes cause air to leak out, causing less pressure. Continuing to rust causes larger holes, till compressor can't fill with air.

My compressor stays on and up to pressure 24/7. I drain it every year or so and get a gallon or so of water out of it every time. That's pretty normal. 

There is an automatic drain valve that will open every time the compressor starts/stops for a couple of seconds to keep them drained. Harbor Freight sells them for about $9. 

https://www.harborfreight.com/automatic-compressor-drain-kit-68244.html

The industrial companies also make a timer-based version that opens every day or so. More expensive but probably more reliable as well. 

https://www.zoro.com/speedaire-auto-drain-valve-drain-size-14-40-gpm-53dn44/i/G7510155/feature-product?utm_source=google&utm_medium=surfaces&utm_campaign=shopping%20feed&utm_content=free%20google%20shopping%20clicks&gclid=CjwKCAjw9MuCBhBUEiwAbDZ-7iH_D0_qh0fkPCrVwoFutPma5u3y0uUxblsBQPhdkQqJjqzc1yD0aRoCg4wQAvD_BwE

I too drain the tank and then leave the drain open after each use. My comp is a 40 year old CH that is very similar to the OP's unit. I've replaced the air filters 2 or 3 times (I try to clean and oil them at least once a year). I also replaced the wheels some years ago. The above, along with cleaning, an oil change, and belt tension check/adjustment every couple of years is all that it has needed.

I'll add this.  Re-route the line from the cylinder output to a water trap first before the air is routed into the storage tank. Better even is to add some extra metal line, such as copper tubing to cool the air and condense the water vapor in the air.  The water trap will then catch most of this water leaving the storage tank with little or no water.  I did this with a new air compressor and I get no, I repeat no water in the tank. 

I changed the drain valve on my Kobalt sixty gallon tank to a ball valve (90 degree open / close) before turning on compressor for the first time. Also added about of foot of clear plastic tubing to a barbed fitting screwed into the ball valve. Thinking was if it's easy to do I would drain tank more often. I simply stick plastic hose into a plastic milk jug and slightly open valve until water runs out then remove hose from jug and open valve wide open to clear any left over moisture. I don't drain tank on a schedule but probably a couple times a month and don't have any problems. I wouldn't worry about a little rust in the water.