Air Compressor question

[A-Jay]

Guys, now I am an Air Compressor Newbie, I bought a used 30 Gal. Craftsman upright unit which is about 7-10 years old. I believe it was used very little. When I was bringing it home I could hear water in the tank. After getting it home I had ran the unit some up to about 80-100 PSI. Then I got the bright Idea to try to drain the tank. I thought by opening the valve on the bottom the water would blow out and make a big mess, but it didn't the water only dripped out. So my next great idea was the little brass valve on the bottom was stopped up like the lower hose drain on the Model A when I drained the Radiator the first time. So I tryed to clear it with a piece of wire, but I did not try very hard because of the pressure in the tank. I thought I might get impaled what ever that means ?

Anyway is this normal for it to only drip with pressure in the tank, like maybe a safety thing? The water was clear I was expecting rusty stuff, maybe the tank is lined. Any thoughts !

[Gary WA]

No should come out with a lot of pressure. open valve fully and use the wire. must be junk in the tank. Goggles and do outside. Messy.Or let air out,remove brass plug start up

[wrndln]

It sound like you might have some rust and crud in the bottom of the tank. I bought a compressor many years ago and neglected to drain it regularly as I don't know you were supposed to do it. The tank eventually rusted out after about 20 to 25 years. I have since bought a large 80 gal real 5 HP compressor and always drain it so I don't have the same problem as the smaller on that rusted through the tank. I would release nearly all the pressure in your tank and then stick a nail or something like that in the drain hole. The water should run out.

[Doug in NJ]

The valve may not actually have an opening in a straight line that would allow you to stick something through it. You may need to drain the air and unscrew the entire brass valve assembly.

Doug

[Dave72dt]

It means it's pretty well plugged. Turn the compressor off, run the air out out of it, then remove the valve from the bottom, clean it, replace it. turn the compressor back on. Opening the valve a little should allow the water to run out. Open it a bit too much or if the water is all out will get you a spray. Close valve. Tanks are not lined that I'm aware of.

[Mitch//pa]

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all good advice above. also keep in mind if need be you can replace your existing drain with a brass radiator style drain cock. a lot of compressors have that style drain.

['29wagon]

that's right , put a 1/4 turn valve on that and a 90 elbow so to shoot all that oiled condensation away from your eyes .
put a 1/4 turn valve on the out to hose before the fitting too, then you can keep it on and not running , those rattle pretty loud .

for removing that existing valve , i'd let the pressure off the top first and put on some safety classes since you don't know what you're looking at .

[Bruce Adams]

Try draining all the air, entirely removing the drain valve and maybe stick something up the hole to permit good draining.
Drain water after each use of the compresor as its instructions probably state.

[Tom Wesenberg]

Don't worry about draining the tank, because after a while the automatic self draining systen kicks in. LOL

I always throw away the screw type drains and install the quarter turn type. They work so much better and are a lot easier to open. The easier it is to drain, the more apt you are to drain it on a regular basis.

[Peter J]

I always open the drain to bleed off the air after I've finished for the day. You don't want to keep your lines pressurised if not in use for any length of time either.

[Herman Munster]

[QUOTE=Tom Wesenberg;184800]

Don't worry about draining the tank, because after a while the automatic self draining systen kicks in. LOL
QUOTE]

Holy Shit, I bet that scared the cat off the ol' lady's lap when it happened.

[cradlescyth]

Hi
Just rebuilt a double lung job. Most have a large plug


on the bottom in adition to the release valve.

Make Sure you release air Preasure!!
remove the plug and clean out.

Check for rust out spots in bottom as they could cause problems
later.
Let dry out -reasemble - test and enjoy..

[Hunter]

Tom,

When I saw the picture and your quote I laughed so hard I had tears rolling down my face. I'll try to stay away from the automatic self draining system.





Don't worry about draining the tank, because after a while the automatic self draining systen kicks in. LOL

[Big D]

Tom,

Agree that would scare the crap outta anyone-- MAX rating means MAX!!!

I took screw plug out of mine and replaced with 1/4 pipe routed to a leg where I welded it (broke off an earlier one on my smaller unit). Put a 1/4 turn valve and a piece of hose (pipe does not have enough give to if attached to something solid) to a vent outside. This helps out when I've painted something by not getting dust in the air. Also helps out with noise of air being released. If you can hear the water then most likely it's plugged up with crap. Also for those who have shop air systems-- I have added a trap on the drop down on each side.. be surprised how much water gets past the filter at the tank.

Just what I have learned over the past 25-30 years owning one.

D

[Honkey84]

Go here > www.garagejournal.com another site ran by Ryan. There are guys over there that have a ton of information on compressors and piping systems. With that said i would remove the plug in the tank after you relief the pressure. Then install an automatic tank drain. I shut my compressor down for the night but leave the auto drain plugged in and let the compressor drain down that way for the night. Gets rid of all the moisture in the tank before you start the next time working.