View Full Version : Can You Make An Old Air Compresser An Air Tank

Dilworth Boy
06-05-2008, 03:18 PM
Can You Make An Old Air Compresser An Air Tank. If So Can Anyboby Tell Me How.
Thanks. :gunsfirin

06-05-2008, 04:05 PM
ooo... this is going to be hard, but lemme try...

take your old compressor, unplug it.


06-05-2008, 04:20 PM
But what if it's gas powered?:jester:

06-05-2008, 04:22 PM
don't turn it on perhaps? lol


06-05-2008, 04:32 PM
Why didn't I think of that. You my friend are a true genius. :laugh::laugh::laugh::laugh:

06-05-2008, 08:48 PM

Where the quick connect (usually female on all the units I've ever worked on) is threaded into the old air compressor, unscrew it from the tank. Let's say it's a 1/4" male pipe thread. Go down to the hardware store, buy a 1/4" pipe tee and a male quick connect end. Thread the tee into the old compressor, then screw the female on one side and the male on the other side.

Take the hose from your compressor and attach it to the male quick connect. Then plug the hose from your tool or whatever into the female. Your compressor will fill it's tank as well as the tank on the old air compressor.

You've just built an accumulator. Better make sure that your new compressor has the cajones to fill it's tank and the accumulator volume as well. Too small a motor and you'll burn it out trying to compress so much.

I hope that's what you were asking....

06-05-2008, 08:51 PM
All joking aside, What was just posted is what you need, might even suggest to add a pop off valve if the original one is missing, cheap insurance.

06-06-2008, 08:14 AM
i would double check the pressure ratings too on the tanks. the old tank may have only been engineered to hold 115 PSI, where as your new one may go up to 175. don't go by the test pressure to get your max. they test up to the test pressure in order to ensure the safety/engineering factor is valid. that engineering factor takes many things into account (humidity, air temp, tank temp, ambient temp, etc.)


Dilworth Boy
06-06-2008, 11:50 PM
I Meant How Do You Run The Lines. :gunsfirin

06-07-2008, 12:17 AM
Look You are messing with a dangerous power source.... If you are asking these questions then please do not do any thing with compressed air. Compressed air can be ver dangerous.

If you want to do something with a compressor tank, then ask questions that tell us you understand what you are doing.

if i pee you off, I am sorry, I want you to live another day.

06-07-2008, 04:06 AM
Any time you are planning to put an "old compressor" tank to a new use you should have it hydrostatically pressure tested. It is not at all expensive and is excellent insurance. You can't tell the condition of an old tank by peering onto a bung on the tank.

I have had several old compressor receivers tested by the fire extinguisher company that I use. The test costs only about $15. Testing is done at about three times working pressure, as I recall. One tank did fail the test, even though it looked fine to me.

If you are talking about a large tank, you may have to shop around for a test facility that can handle the size.

Be safe.


06-08-2008, 05:17 PM
sorry... i didn;t want to seem like a smart-a$$... just couldn't resist.

on a more serious note, it can be done fairly easily. take a few fittings and plumb them together is the easiest way... try to keep a flexible piece in the connection tho, in order to keep cracking due to vibration to a minimum.

here's what i would do: go from the outlet of the good compressor, and add on a connection from the quick-connect to a flexible air hose (obviously rated for the pressures at hand). run that short (6-12" long) piece of hose to a "T" fitting. from one end on the tee, go directly to whatever other fittings you need in order to attach it to the outlet on the old compressor. the other end of the tee can run to your existing air distribution system (hose, tools, etc.).

some people will tell you to take the pump and motor off of the old compressor. after you hook everything up, if it will not hold air, or you want the motor/pump for something else, THEN remove it (obviously after purging). unless there is a bad check valve in the system, you will have no problems with holding air in the old compressor.

there are many ways to skin a cat... this is just the way i would do it.


06-23-2008, 10:53 PM
take off the motor and just put female adapters where ever there is a hole for it.

08-09-2008, 09:37 PM
Please be sure you retain the pressure relief valve. That thing is a bomb without it.


08-09-2008, 09:57 PM
Please, stop messing with this thing!:blob2:
You need somebody to show you.

08-10-2008, 03:13 PM
So you guys are saying an old compressor tank is dangerous? I have an old Sears air compressor probably from the early '80s. It has developed a small leak on the bottom. I think it's starting to rust out a little. I've been using it regularly for the past couple of years. Should I stop using it?

08-10-2008, 03:22 PM
if the tank itself is actually the part that is leaking, then yes. the engineered wall thickness has been damaged and is no longer to the engineering specs. if it just a fitting (say the drain threads have started to leak a little), then see if you can just put some teflon tape around the threads and you should be good.

in short, if the thing is leaking, then YES!!! STOP USING IT!!!. at least until you find out what is wrong with it. you are talking about a significant about of potential energy here. if and when that thing blows, there is a good chance that if the sudden air pressure change within the shop does not knock out the windows at the very least, then the shrapnel will probably kill someone. think of a pneumatic grenade of sorts.


08-10-2008, 04:49 PM
Pay attention to what aczeller is telling you! If anything, he is not emphatic enough about the danger of a compressor tank that has begun to leak. If it is the tank bottom and not the fitting threads that are leaking, the leak reveals a dangerous degree of weakening of the bottom of the tank due to corrosion, probably the result of not rigorously draining the condensed water out of the tank after each day's use.

Your life or health and property are not worth the few tens of bucks you are saving by using a corroded tank. If it is the tank and not the fitting that is leaking, you should take a fire axe or pick to it so nobody is tempted to try using it again.

Whenever I put a tank of unknown history to use I have it hydrostatically tested at a local fire extinguisher service company. Cost was only about $15 for the last few I had tested. One was condemned and I had them junk it.They test to (I think) about 3 times working pressure.

The other factor to keep in mind when considering putting an old tank to use is to consider using only an ASME rated tank. They are built to specific quality standards with certified welders and inspection at various stages so you know it was built to certain quality standards to begin with. You will find an ASME coupon welded to the wall of the tank. Of course, an ASME tank can rust out just like a non-rated tank, so always have it tested.


Oh! Wait! You were kidding us, right?

08-11-2008, 07:36 AM
Thanks guys. My tank isn't leaking at the drain fitting threads. The tank itself has a pin hole leak. I'll definitely stop using it. It's too bad because it's a nice compressor and it still runs good after all these years. I remember my dad using it when I was a kid.

08-11-2008, 08:19 AM
Keep an eye on craigslist for a broke oiless compressor and grab the take of one. I see them fairly regularly around here for anywhere from free to 50 bucks...Make a bbq pit out of yours.