Air in Beer Line

[WalterEgo]

I have been using my converted 'fridge MM system for about 4 years with no problems, about 96 1/4's of Yuengling Lager. I recently changed my lines and have a problem with air getting into my beer line.

After I pull a beer I can see a "fountain" of air bubbles coming from the stem of the coupler. It forms an air pocket in the line when that air pocket is forced out by pulling another beer it causes a great deal of foam behind it.

I have tried lowering the keg pressure to the point that it barely flows and increasing it to 11+ psi. I get the same result either way. I have removed and replaced the clamp holding the beer line to the stem.

I got a new keg coupler thing that first had finally gone bad - no change. Connected a brand new keg tonight and as soon as I locked the lever down it started, before I even opened the airline from the tank.

I have been using a work-around by letting the first few ounces go into a jar and then filling a glass after that but I'd really like to have some idea what is going on.

[PointPleasantNJBeerguy]

Where are beer temperatures pouring at?and do you know if your co2 is secure from tank through regulator?

[pvs6]

Please verify this timeline. The old keg kicked, you then installed the line and got this new keg and now have gas seepage. If so I am inclined to suspect a bad Keg firstly and it's just coincidence that you changed line. There have been 2 members here recently with bad kegs and if these things come in 3's you might be the last we heard about it for awhile. I've never had one myself but it does happen. Un-couple and inspect the gasket on the keg top and the coupler for nicks, tears or any thing not seated properly.

If the seepage is coming out of the top of the coupler it's not a bad beerline to stem connection that flaw causes beer and gas to leak out on top of the keg.

"I got a new keg coupler thing that first had finally gone bad - no change. Connected a brand new keg tonight and as soon as I locked the lever down it started, before I even opened the airline from the tank."
Couplers (metal) rarely go bad. The plastic gas check valve, beerline check valve and the neoprene gaskets could ware out given enough time. What did you replace in regards to coupler? It's cheaper to just rebuild them.

Don't change the pressure to correct foam. Learn or ask what the correct psi is per keg and never deviate from it, it only makes things worst in the long run. Better to do you're work around, burp the line into separate vessel then pour pint, about half gone the foam settled into beer that can be added to the pint.

[KillianBoy]

WalterEgo,
I don't think air is getting INTO system, stream of bubbles usually means that PSI too low and is breaking out of solution.
"I got a new keg coupler thing that first had finally gone bad", no idea what this means, if this means you have a new coupler, make sure everything is hooked up correctly, make sure the line is 3/16 ID and is true beer line, should be 6 feet +.
As PointPleasantNJBeerguy says make sure you are balanced to temperature, if PSI too low CO2 will breakout and cause problem described. Normal way to tap is make sure tap is in off position, open tank, open regulator valve, tug on pressure relief valve on coupler, you should hear a hiss, no hiss, no CO2, if hiss then open coupler. If still bubbles after you balance try flashlight test (up PSI till bubbles stop).
If brand new coupler leaks near tailpiece (connection between tailpiece and coupler near hex screw) make sure you have a neoprene washer between tailpiece and coupler (actually the check ball retainer), if leaks at tailpiece and beer line, line might be too large, if stem you mention is tailpiece and leak is here and clamp doesn't seal, line might be too big.
Next post, can you be clear in parts and EXACTLY where you see leaks in system and again beer temperature, PSI and beer served and/or v/v of the beer.
KB

pvs6 beat me to the punch but I don't think he had 2 bad kegs in a row (but possible), make sure you have all the parts where they should be and hooked up right with right gear, please post back when and if you find problem.

[pvs6]

I don't get this notion people have that air can leak into the delivery system from a lose connection. Even at just 1 Psi in the system that's still higher pressure than any atmosphere above sea level. Nothing can get into the system it can only exit out of the system. Don't believe science try it for yourself. Dual the reg down to 1 Psi and open the release valve. Note air does not flow into the valve Co2 hisses out.

[WalterEgo]

It pours at 37 degrees. The air line is secure, I replaced the regulator a few months back and check the connections every time I change kegs.

[WalterEgo]

PVs6, thanks for the catch on the name.

My timeline is; is after several years with the original setup, and having replaced only the single dial regulator for a double, I decided to change my beer line in anticipation of the arrival of a sixtel of Nugget Nectar. The line I used was the same as the original 5/16 ID from MM. When I hooked up the Nectar this problem started. I assumed a bad keg, no big deal, I have my workaround.

So the Nectar kicks and I go back to my standard, same situation. I look over all of my connections, re-apply clamps, nothing helps. I see the coupler has some wear on it, the seating gasket seems fine but I buy a new one anyway.

That keg goes so I install the new coupler, get a new keg and I am still in the same boat. I tried reducing the pressure just to see if it helped. I pushed up the pressure as a test. All the same either way. I can see bubbles coming up into the line out of the stem.

The workaround is fine but it bothers me that everything was fine for so long and I seemingly screwed something up by messing with it.

[KillianBoy]

WalterEgo,
If you are not leaking beer, your system should be fine, if new coupler and keg and you are still having a line of bubbles from coupler, then PSI might be too low. Changing beer to different brewery might be the problem, look through forum regarding balance, every beer is carbonated differently, Yuengling Lager is listed at 2.6 v/v, call Troegs brewery and ask what their v/v for Nugget Nectar is, mostly likely higher than Yuengling and causing this CO2 breakout from beer. You should try and remove the check ball, set PSI to beer v/v and see where that gets you, also what kind of beer is Nugget Nectar?
KB

[djc]

Are you sure your original line was 5/16ths? Normally you would see 3/16ths in this application. Could you have replaced 3/16ths with 5/16ths?

This is what NN is.... http://beeradvocate.com/beer/profile/694/15881

You won't see that in HI.

[KillianBoy]

WalterEgo,
I concur with djc check the line, I assumed it was a mis-read of the OD vs. ID, don't think that is the cause of the problem.
OK, so both Yuengling and Troegs have the same problem, with new regulator and new coupler, AND new keg, not really sure what the problem could be. The biggest problem is that you changed this, then that, then changed beer, then changed back. I would try to adjust the PSI low, then high (18+), then low again, then high, see what the bubbles do, if nothing happens might be regulator or check valve. If you used the same check valve on new and old coupler see if the lips are sealed up, your symptom sounds like low PSI. You could try without the check ball, but 2 bad ones unlikely.

djc,
I saw pictures of it but was confused, it kinda looked like a Hefe but found it was an Ale, don't know. Last American Ale I had was the Hawaii Nui Sunset, it was dark brown. I think I may have tried a Troegs brewery before, a long time ago, store here carries a bunch of odd beers from the lower 48, not consistent and expensive.
KB