king keg question

[Dronfieldbrewer]

I have 2 king keg top taps. Both of which are a nightmare to seal, goes great for the first week after a smear of Vaseline on the ring (fnarr fnarr)! But then the pressure just drops. I give it a squirt of CO2 from an S30 jobby and can hear it hissing from the top. This happens to both kegs.

I have tried new seals, I have vaselined the top seal in a big way. I have tried to tighten the top to a point that only a gorilla will be able to loosen it but all to no avail. I don't really want to chuck them but I could do with them working properly especially now that I can fill either both kegs with 1 brew or a corney and a keg plus 20 bottles in one go.

Any ideas other than send to tip in favour of a few more corneys

 

[jonnymorris]

You mention a gorilla... have you tried a strap wrench? Whilst over-tightening probably isn't a great idea, it works for me.

That and loads of vaseline.

 

[Kev888]

There can be several causes of leaks, unfortunately.

As it seems to at least hold some pressure to start with, one that it could be is injecting gas can cause frosting under the internal rubber on the S30 valve and stop it closing properly until it thaws. Shorter/briefer blasts will help that.

The mold-line around the barrel extends over the top; in some cases this can leave a small raised bit of 'flash' that stops the lid's O-ring sealing - it can be trimmed off with a sharp knife but make sure you don't dig in as a crevice is just as bad and harder to solve.

Vasseline helps because it stops the lid dragging/distorting the O-ring as you tighten it. BUT as it also makes the lid easier to turn, it makes it easier to over-tighten, which can also distort the O-ring and break the seal. So don't overdo it - it may be counter-intuitive but you can over-do it.

Sometimes the valve itself can be loose in the lid; gas leaks out around the valve/lid seal.

If you spray some starsan or washing up liquid or something around the lid and valve after injecting it may bubble up and help narrow down where the leak is.

Cheers
Kev

 

[Dronfieldbrewer]

There can be several causes of leaks, unfortunately.

As it seems to at least hold some pressure to start with, one that it could be is injecting gas can cause frosting under the internal rubber on the S30 valve and stop it closing properly until it thaws. Shorter/briefer blasts will help that.

The mold-line around the barrel extends over the top; in some cases this can leave a small raised bit of 'flash' that stops the lid's O-ring sealing - it can be trimmed off with a sharp knife but make sure you don't dig in as a crevice is just as bad and harder to solve.

Vasseline helps because it stops the lid dragging/distorting the O-ring as you tighten it. BUT as it also makes the lid easier to turn, it makes it easier to over-tighten, which can also distort the O-ring and break the seal. So don't overdo it - it may be counter-intuitive but you can over-do it.

Sometimes the valve itself can be loose in the lid; gas leaks out around the valve/lid seal.

If you spray some starsan or washing up liquid or something around the lid and valve after injecting it may bubble up and help narrow down where the leak is.

Cheers
Kev

Righty ho...this is brilliant Kev. Once I have traced the leak, then what? Is it a case of new seals or pillocking about until this one sorts itself....

I have used nearly 1/2 jar of Vaseline on one seal to get it to seal. It's if the pressure in the barrel just blows the vaseline away. I, However, will not be defeated by a bit of bent plastic...(that's what I tell the wife)! I will peruse this until the seal works....

 

[Kev888]

If its blowing the vasseline out then it does sound like a leak around the O-ring (assuming thats where the vasseline is). The purpose of the vasseline is really just as a lubricant for the ring (as it were) and sometimes the threads, rather than as a sealer itself, so you don't really gain much by using loads of it.

Its the ring that needs to squish smoothy between both the lid and the top of the barrel neck to form the seal between them, so leaks here are almost always due either to defects in (or crud on) these surfaces or the ring itself, or because the ring is being distorted due to over-tightening and/or insufficient lubricant. Its also possible to cross-thread the lids, but thats pretty obvious as it goes on cock-eyed.

I'd say the first step should be to check for anything thats not right; flash around the mold line across the top of the neck where the ring sits, other defects (crevices, lumps, splits) in the top of the neck or in the plastic lid that could stop the ring sealing to it nicely, and the O-ring can become quite easily damaged too when diging it out of the lid for cleaning/inspection, so check that its okay.

If you do spot anything take care in how you deal with it - sometimes people have over-done removing flash for instance, and caused a crevice or deep scratches instead.

Cheers
kev

 

[Wezzel]

Don't overdo the Vaseline but just give it a light smear.

Tighten the lid hand-tight, give it a quick burst of gas and listen for leaks. If you hear a hiss tighten the lid a little until it stops. Leave it for a few hours and check its still pressurised by squeezing the pressure valve. If all okay, release most of the pressure via the valve and then leave it to condition.

You can always give the valve a little squeeze or open the tap a fraction every few days just to be sure.

Recently. I fitted car tyre valves to the lids of my kegs so I can check the pressures with a cheap digital tyre gauge.

 

[Triker]

I know this thread is a few months old now but I have had problems with the KKTT too. I've been reading a lot of forums and it appears to be quite common.

One of things I've read has already been touched upon regarding the use of vaseline. A smear rather than 'loads' is enough but it has to be in the right place. It is important to remove the 'o' ring seal and smear vaseline all over it so that when you tighten the top its doesn't distort on the suface between the keg or the top itself.

One of the major causes of leaks appears to be that the keg 'rim' isn't smooth enough, or isn't 'flat' enough! I have just done mine and it was at least 1mm higher on one side. I marked all around the keg rim with a permanent marker. Then you need a piece of glass (or similar 'flat' material that won't distort) bigger than the top opening. Start off with a sand paper (not too rough) and work in a circular motion. Not forgetting to 'turn the keg' as you go to avoid taking too much off one side. After just a few strokes check it for 'low spots'. Keep this up until you are certain that all the 'high spots' have gone. You should now have a 'flat and even surface'. All you need to do now is finish off your handiwork with some 2000 grit paper to get it really smooth. Now your vaseline can really do its job.

Another thing I picked up was to drill a hole in the float as on this thread courtesy of pjbiker viewtopic.php?f=23&t=16258 This really helps to prevent using too much gas!

I think the tyre gauge idea by Wezzel is excellent. Why didn't I think of that :clap:

 

[artyb]

ive been lucky with my two k\kegs, :party:

i ''just'' tighten the lid ,so the seal does not distort,
the top of them look pretty good... :hmm:

i have drilled a hole in my float.. but oppersite the pipe, it helps to keep it in the brew, never had any problems tbh..

 

[Triker]

Don't overdo the Vaseline but just give it a light smear.

Tighten the lid hand-tight, give it a quick burst of gas and listen for leaks. If you hear a hiss tighten the lid a little until it stops. Leave it for a few hours and check its still pressurised by squeezing the pressure valve. If all okay, release most of the pressure via the valve and then leave it to condition.

You can always give the valve a little squeeze or open the tap a fraction every few days just to be sure.

Recently. I fitted car tyre valves to the lids of my kegs so I can check the pressures with a cheap digital tyre gauge.

Hi Wezzel,

Its just dawned on me that tyre valves are normally sealed from the inside with a rubber solution so how do you seal the valves in your keg? :hmm:

 

[Kev888]

I can't speak for wezzel, but in case its of use I recently got some motorcycle bolt-in ones to fit into PET bottle caps (here).

Cheers
Kev

 

[Wezzel]

They would be fine. The car valves I used are tapered with a recess that the cap fits into. You need to drill a hole about 12.5mm diameter, lubricate the valve with some soap or Vaseline and pull them through until the tapered bit is pulled through the hole and splays out again. They are difficult to pull through and the tyre shops use a threaded valve puller. I just wrapped the threaded part with some rag to protect it and gripped it with a pair of pliers. It works fine and doesn't leak. I have done three so far.

 

[Triker]

Thanks guys.

As always... great tips
:thumb:

 

[Dronfieldbrewer]

An update for you....Lost patience with them and went to homebrew shop in Doncaster...Alan there is a brilliant bloke and less likely to kick the kegs over the roof than I am....

3 days later quick call from Alan. He put some new seals on both kegs and can confirm that they have held pressure overnight.

In the meantime, I have bought a new corney keg, regulator and gas bottle so have loads of space now to fill with delicious beer...

I now have:-

150+ magners bottles (local pubs were a bit busy over xmas)
2 King Keg top taps
2 Cornelius kegs.

So will be brewing like a wotsit over the next few weeks to get this lot filled...I intend to brew 50-60 litres per brew, pop into corney or K K and bottle rest until all is full

 

[AllvinStraight]

surely ptfe tape(aka plumbers tape) around the threads will cure a lot of these leak issues(I hope! as I have just bought a king keg but not used it yet)