Loose dip tube....wtf

[hoppheadIPA]

I have a brand new ball lock keg and no matter how many times I re-seat the dip tube and post, the tube remains loose. When the post is tightened, you can reach in and shake the dip tube around. I even swapped sides with the other tube. Changed the seal already too. The keg hold pressure though, which is weird. Any advice?

 

[GilSwillBasementBrews]

My only concern with the serving side is if it loose would leave me to worry about co2 escaping the headspace into the serving line.

 

[hoppheadIPA]

This is exactly what I'm scared of.....any thoughts of how to fix it?

 

[GilSwillBasementBrews]

The only thing I’d recommend is replacing the o-ring under the rim of the tube. But it sounds like you already tried that.

 

[balrog]

not sure how the keg can hold pressure if tube and its o-ring are loose under the out-post.
THen again, I've never checked my dip tubes after tightening the posts.

And no kids, that's not a euphemism for anything.

 

[hoppheadIPA]

The only thing I’d recommend is replacing the o-ring under the rim of the tube. But it sounds like you already tried that.

Yeah, already did that....maybe something with the post? Spring may be short?

 

[GilSwillBasementBrews]

not sure how the keg can hold pressure if tube and its o-ring are loose under the out-post.
THen again, I've never checked my dip tubes after tightening the posts.

And no kids, that's not a euphemism for anything.

The poppet in the post will seal the post thus the keg will still hold pressure even with the dip tube being loose

Yeah, already did that....maybe something with the post? Spring may be short?

Might be a shorter spring on the poppet. Maybe newer oring is flatter than original. Maybe try a fatter oring?? I’d say double it and see. But then again not sure that would seal properly

 

[day_trippr]

The poppet in the post will seal the post thus the keg will still hold pressure even with the dip tube being loose[...]

Did you mean that the poppet spring will put enough downward force on the dip tube to seal?
In my experience that's definitely not a truism...

Cheers!

 

[GilSwillBasementBrews]

No I was thinking the poppet would seal to the post just as it does to prevent beer spraying out.

 

[balrog]

Poppet top seals top of post to outside.
I guess threads have to seal against keg. Never thought that hard about it.
But in between threads and poppet top, you can have dip tube with no o-ring I guess, if the threads seal, and they have to, regardless of the dip tube o-ring. It's all open in there between threads and poppet top.

 

[GilSwillBasementBrews]

That was my assumption. As when the oring is bad it allows co2 into the beer line when serving. Yet the keg remains pressurized.

 

[day_trippr]

Wth?
Here's how dip tubes on corny kegs work:

• The small O-ring under the dip tube flange is compressed as the post is tightened down.
• As the O-ring bulges outward, the expanding outside circumference seals the inside of the post to the dip tube flange.
• Meanwhile, the same O-ring resting atop the threaded riser seals the bottom of the flange to the keg.

I have 16 ball lock kegs (all well used before I got them) and none of the dip tubes can be easily moved around.
Who made the keg in question?

Cheers!

 

[GilSwillBasementBrews]

I’d listen to him^ he’s much more knowledgeable.

I never really gave it much thought. Just assumed since I’ve had bad orings leak co2 into serving line and not leak beer or pressure out of keg, that the post sealed via the threads to the threaded stem under the post. Again. Listen to trippr.

 

[hoppheadIPA]

I dunno who made it, I'm not at home right now. But the thing is basically brand new. I've served one beer out of it so far and it poured awfully slow compared to the other kegs in there, same pressure......I wonder if this is related?

 

[Bobby_M]

The diptube just has a bit of extra clearance in the bore. It doesn't matter how snug the oring because that remains a soft pivot point. No need to worry.

 

[day_trippr]

And that is indeed the bottom line: if the dip tube/small o-ring/post/etc manage not to leak CO2 into the keg headspace (where guar-an-teed it'll screw up the pour) then it's all..."benign".

That allowed, I'd still like to know who the manufacturer is that couldn't at least duplicate the tolerances found in a 60 year old design if not improve on it...

Cheers!

 

[JAReeves]

You may have already done this, but once you seal it and pressurize it, check it with Star-San around the post. If it's leaking, you'll know.