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Excessive Foam

Here is the situation. I have 4 kegs running all on the same pressure and of nearly the same gravity. One of the 4 is giving excessive foam and there is foam in the line. I can here the foam forming when I pour. It sounds like it is coming from inside the keg. The other 3 kegs make no sound at all when poured. It seems like a restriction in the line somewhere. This is the first use of this keg and I did do a thourough cleaning, including a tube brush.

I’m thinking of just doing a keg transfer and let it set a few days before tapping again.
Any thought or ideas on what might be going on? I should add that I am fairly new to kegging.
(Oh, I love kegs :lol: ).


Check a different keg on the same line to rule out line problems. Also you might want to check what vol it should be at for the type of beer it is. Beer can foam differently depending what type it is.

Hook the ‘bad’ keg up to a ‘good’ line and see if it still foams. If it does, you’ve isolated the problem to the keg, specifically on the beverage side. Most often this is caused by a hop particle or something that is clogging the dip tube. You can try blowing gas through the tube to clear it, or just remove the dip tube and inspect. Also can be due to a bad o-ring seal, like from a loose post or a knicked o-ring. Check both - under the dip tube and on top of the keg post. Also check that the poppet can move freely and is not clogged.

Less commonly, there can be a crack in the dip tube where it flares out at the top, which will allow CO2 to enter the beverage line and cause foaming.

I think overcarbonation is unlikely unless you have done something different with this batch?

I should have been more thorough on my original post. I did try a different keg on the same line. All are carbed in the sit-forget method at 10 psi. I have 4 kegs running off the same manifold and they all fall under the same range on the charts for carbing. I’m starting to think something is stuck in the poppet. The noise that the keg makes when dispensing and the foam in this out line is what bothering me (along with the excessive foam in the pour).

I’ll take out the dip tube in the morning and inspect o-rings, poppet, etc. I’m thinking that is what it must be. The noise when dispening sure sounds like some kind of restriction. There shouldn’t be any hop particles as all my beers are racked to secondary in carboys and I really don’t even have much at all for hops in the primary.
Thanks for the replies. I’ll let you know how things work out.

Update - I finally figured out what the problem was. So I thought I would post it in case someone else ran into the same situation. I had given up on the problem until the keg kicked and had resorted to using a pitcher to let the foam settle out. Well today the keg kicked. After trying different outlet posts and different serving lines, the problem still existed, even using clean water. What was happening was that CO2 was getting around the o-ring on the dip tube (the o-ring was new with keg lube on it too). I simply doubled up on the o-rings and no more foam. At least I can use that keg again without any worries. It was my first use of that particular used keg.

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