keg pours all foam

I hope someone can help me with this problem because I'm stumped. I brewed a 10 gallon batch of IPA and split it between two kegs. Both taps on my homemade kegerator are exactly the same (10ft of 3/16" line, perlick 525ss taps). I have a two product taprite regulator and put both kegs through the same carbonation schedule (30psi for 24 hours, 20 psi for 24 hours and then serving pressure of 12psi at 38 degrees). One keg was carbing up noticeably quicker than the other, so I drank from it exclusively, and it was pretty much perfectly carbed by the time it kicked. I then started drinking from the other keg, and it was still basically flat even though it had been on co2 the whole time. I thought there might be a problem with that leg of the regulator, so I switched the beer and gas lines from the first keg to the new one. It did seem to start carbing up better after that but just as it started to develop some bubbles and a nice head it went almost completely to foam. Literally one pour was almost acceptable and the next pour was 3/4 foam. Then the foaming problem just continued pour after pour.

I thought that there might be some kind of restriction in the dip tube or liquid out post of the new keg that was stripping out CO2, so I switched them with the ones fist keg to see if that would help, but it didn't. I don't think the foaming could be from overcarbing or warm beer lines, so I'm not sure what else it could be. They only way I'm able to get even half a glass of beer without excessive foam is to drop the regulator to around 4psi and let it trickle out. At this point, I'm think I'm just going to push the beer to another keg, but does anyone have any ideas might be wrong with this keg in particular or think of anything else I can try?

 

Do you see foam in the beerline?

 

My first thought is a leak somewhere. I had the same problem on found a bad gasket on the gas post.

 

Maybe a bad o-ring between the beer out dip tube and threaded stud. This would allow CO2 from the headspace to enter the stream of beer on the way out.

 

Have to agree with this.

 

I don't see any foam in the beer line as far as I can tell

I was wondering about that too. The liquid out stud on this keg is dented in a little, so maybe the post is not able to seal. If that was the case, would the keg still be able to hold pressure if both the liquid and gas lines were disconnected?

 

Add 10' to each line maybe? Drastically helped my foaming issue...that and a computer fan circulation air and disrupting the temperature stratification.

 

A couple of my kegs have keyed diptubes. The diptube has an elongated dimple/slot that must be lined up with a key in the threaded stud.

Pressure can be held even with a bad diptube o-ring.

 

This must be my problem then. I used the diptube oring from the first keg when I switched the tube out, but maybe the stud on this second keg is too far dented in for the liquid out post to seat properly. I may just have to use this keg for spare parts and save myself the frustration.