Keg Pressure Tester

After going through two co2 tanks and thinking I fixed the leak both times I got sick of wasting co2 so I made a gadget to pressurize kegs with my air compressor. I got a $20 tire filler that used a 1/4" id hose and cut the filler hose off so I could put a barbed mfl connector on it. I threaded that to an mfl disconnect and it connects to an empty keg so I can put pressure in it and then spray some star San around the fittings.

Can anyone think of a reason this is a bad idea? I'm not using it to add pressure to beer, just empty kegs since it would obviously oxidize the beer.

That sounds like a great idea, certainly save on the c02. If you used to pump your beer up it would probably stale faster due to 02, but for just testing seals I like it! I've had the best luck putting a star san mixture into a little spray bottle and just hitting the whole top of the keg to find a leak. I have also once put it in the tub on one where I thought there was a leak, turned out that the leak must have been in my manifold or hose, the keg was fine.

Just a note that might help. I've had kegs leak at 5psi, but once they go to 10, they are sealed. I've also had a keg leak only on the air in poppet, so when it's hooked up it's fine. But if I take the keg out of the fridge and leave it the whole thing goes flat.

Good luck!

Smart way to test the kegs. Don't see a down side unless oil gets in there.

Make sure you are using an oil-less air compressor, otherwise you would be blowing oil into your keg.

I have a moister trap on the outlet of the compressor. Will oil make it through that?

My understanding is some oil will get through. It's not much but I wouldn't risk it.

I made something similar, and also use it to push sanitizer through the lines. instead of a compressor hookup, I used a valve stem from a bicycle innertube. It connects to my bike pump, and I can use it to test kegs, pressurize them to transfer fluid, or whatever else I can think of.

put a pressure regulator and relief valve on there, your compressor can easily exceed the safe limits of a keg.

Excellent ideas there. I might do the same.

Reynolds, the kegs have a pressure relief valve built in. Also, I'm only setting the compressor to about 40psi, nowhere near the max working pressure the keg is rated to. The tire filler also has a gauge built in and I haven't gone over 30 psi. I don't see much danger since I force carb beer at 30psi.

Agreed, you're pretty safe. I would still want a relief valve in case something goes wrong that includes a failure of the built in relief valve.

Yes, oil and moisture can still carry over past your separator.

For a decent filter, Google "Motor Guard" air filters, it would make a good filter for this task, and you can use a roll of toilet paper as a replacement element.

Another option would be a filter for painting a car, though they can get PRICEY!

Check "NAPA", as you can find decent prices there sometimes.

Element filters will not filter all the oil out, regardless of composition. There will always be some oil in the air unless you use a three stage coalescing filter system (expensive).

If you don't want to use your co2 to snoop for leaks; then you'll need to wash the kegs, seals, and all fittings inside and out with a good nontoxic surfactant such as simple green.

I use a similar set-up. Saves a lot of CO2 when cleaning kegs and running cleaner/sanitizer through my keezer. I used a disposable filter from eastwood in line with an air gun and an adapter to a ball-lock fitting. It has 1/4 pipe fittings on both sides and I've had no issues with oil. It looks like this...

Having a kegging issue I, too, made a keg pressure tester using a gas disconnect and a pressure gauge.

Mine is a bit more ghetto, though! And yes, 37 PSI was correct.

Just a heads up, a leak at 37 psi may not show it's ugly head, until the pressure drops to 12psi. My corneys can be such a PITA, The poppets are forever not seating well. I hose everything down with star-san in a spray bottle and watch for blowing bubbles. I'm switching to sanke kegs.

mikescooling said:

Just a heads up, a leak at 37 psi may not show it's ugly head, until the pressure drops to 12psi. My corneys can be such a PITA, The poppets are forever not seating well. I hose everything down with star-san in a spray bottle and watch for blowing bubbles. I'm switching to sanke kegs.

Click to expand...

Thanks. The 37 PSI was just for some carbonation troubleshooting - no leak issues. (https://www.homebrewtalk.com/f35/help-my-carbonation-issues-432464/).