King Keg - Leak through pressure valve even though it's new - the valve is new,that is

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PaulQQQ

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Hello,

I've inherited a King Keg with the high tap from a retired brewer and am checking it before risking a brew but I've found a problem.

It came with two caps, one of which had the sparklets type valve. When I tested this cap by filling the keg with water and putting it on it's side then water came out of the filling valve hole (no sparklets cylinder attached) at this time. I then added a sparklets cylinder but unfortunately the keg wouldn't hold the pressure.

My local brewshop suggested fitting a new valve so I added this to the second cap - the problem is that the same thing happens. If it's upright it leaks gas out of the filling valve hole where the cylinder fits. I've put water over the hole to verify this and can see the bubbles. Fairly soon enough leaks out for all pressure to be lost.

So, it appears to me that it might be a valve rubber problem - I'd expect it in the first cap with the old valve which is quite old and hasn't been used for a while but I'm a bit surprised to get the same leak from a new valve. These valves seem simple - just two holes with a valve rubber on the inside filling side and also on the over-pressure outlet outside. It seems a bit odd to me to be getting the leak from the new valve with (hopefully ) new valve rubbers.

Would anyone have any experience of this? Are dodgy valve rubbers a problem even in new valves?

It doesn't appear to be leaking around the cap hole as I've tested this with a bit of detergent around the hole to identify bubbles. Also the cap o-ring is new and seems to work ok. I've tested this by filling the barrel about 7/8 full with water, putting on it's side so that the air bubble is above the cap and tap and then pressurising it with a new sparklets cylinder (i.e. they're in contact with the liquid rather than the gas) and the cap appears ok, as does the joint through the cap.

If anyone can offer their thoughts I'd be grateful.

Paul
 
Hi @PaulQQQ , it sounds like the non-return valve rubber needs replacing. Apparently they can be faulty from new depending how long they've been on the shelf and how they are stored. The safety/pressure relief valve has the same problem. Some KK users on here regularly change the rubber bands on the valves, remembering the trick with a cable tie on the non-return valve. Good luck.
 
Probably the inlet valve (little, normally black, one on the inside of the cap. All of the seals should be replaced regularly as they become brittle over time, especially if in contact with sodium metabisulphate...
 
Where, exactly, is the leak? Yours may not have part 1
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Many thanks all for your replies.



Given Kelper's diagram above I do have part 1, the piercing pin insert, as it's a new valve, and the gas does appear to be leaking through the hole in part 1 - which does suggest the valve rubber is not working properly. I'll replace both valve rubbers and see how it goes. If that doesn't work then it is probably the inner o-ring but as I can initially pressurise the keg (before the gas leaks out through part1) then I guess that's ok for now.

And now for a few follow-up questions:

  1. Are there any useful techniques for getting the valve rubbers on? Are they quite stretchy when new? I imagine so and they must just stiffen with time.
  2. Buffers Brewery's response mentions the old trick of using a cable tie - I've not heard of this - could someone explain it to me? Explanatory pictures might help.
  3. Finally, would anyone know if I can get a single valve rubber kit and 'o' ring kit with all sizes of valve rubber and an inner 'o' ring for the pressure seal - I've seen them sold separately but that way adds to the cost of buying? I'm trying to keep my budget low.


Many thanks again for any help given.

Paul
 
the old trick of using a cable tie
The small rubber band on the spindle under the cap, item 5 on @kelper diagram, can and has blown off the spindle during re-gassing rendering the non-return function useless. So the trick is to get a small cable tie and fit it at the bottom of the rubber just above the lip of the spindle.
AA5773B4-A9EE-41CD-B3FE-8834422B7B66.jpeg

Excuse the state of the brassware. Came from my “scrap box”.
any useful techniques for getting the valve rubbers on?
When new the rubber is not very stretchy and fights back! I used to use a small watch makers philips screwdriver trying not to scratch the brass surfaces and wind the screwdriver around while swearing at the rubber.
 
Maybe a straightened out paper clip (coz it's bendy) put inside the rubber might work, as you could keep the sharp ends clear of the valve rubber seating and avoid scratching it. by slowly working it around in circles it might get the valve rubber on..?
 
I had a similar thing with a new S30 valve - my old one was leaking as it had sat unused for four years. Bought a new Hambleton Bard valve, and refitted it in the same arrangement as the old valve, with the seal on top of the lid. It held pressure for a few minutes, then leaked down to atmosphere. After some head scratching, I wondered if the seal should go on the inside with this type - so underneath the lid. Tried that, and it's held pressure perfectly since then. The Hambleton Bard has a collar & the securing nut screws down from above, while my old valve had the nut below. Worth checking which type you have.
 

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If you put the washer inside, it's more likely to get squeezed out as you tighten the nut. On my 5 KingKeg caps the washers are all outside.
 
If you put the washer inside, it's more likely to get squeezed out as you tighten the nut. On my 5 KingKeg caps the washers are all outside.
Pictures I have found online, as attached to my post, show the seal inside the lid with the Hambleton Bard valve. If the seal is outside, the pressure relief collar only seats on a thin part of the seal, with pressure able to escape from inside up past the collar internally. Certainly mine leaked until the seal was located inside.
 
I've never had to change a seal but I do have the special pliers to stretch the rubber. Seal kits are available from Ballihhoo and others.

https://www.brewstore.co.uk/home-br...rrels-and-barrel-spares/s30-valves-and-spares
https://www.ebay.co.uk/itm/Elastrator-Pliers-Rubber-Ring-Applicator-100-Pcs-Rings-/130589011384
Hellerman Pliers are three fingered not four, and are more suitable for stretching the blow-off bands than ones designed to wither lambs knackers and tails. Still expensive though. The smaller inlet rubber will only blow off if you are heavy-handed when adding gas.
 
Hi All - I may have found the problem. I eased off the inlet 'no return' valve rubber and found that the hole drilled crossways through the valve block hadn't been finished properly - where the drill came out a sharp pointed edge (it might be called 'flashing' )had been left which I'm guessing had punctured the valve rubber. Ideally this should have been filed away during manufacturing. Anyway my local retailer changed it for me and I'll try again ... I'll keep you posted.

I found the handle of a small teaspoon helped get old valve rubbers off - it might be preferable to a screwdriver as it doesn't have sharp edges which might score the valve and cause future leaks (I hope!). Wetting it a bit helps too to provide some slipperiness. A pin is the best way of getting the o-ring out of an old valve - you pretty much need to impale the o ring so you can't re-use it but they're finicky to get at at the best of times.
 
Late to the party - with the discussion on putting the Inlet Seal Rubber has anyone suggested using a Pellet Banding Tool ?

I use one for fishing to (of course no s**t Sherlock) Band pellets and they have 4 arms and stretch a band over a Pellet. Sure there are anglers on here who will have suggested them - and they might not be strong enough anyway

PS Just searched and found nothing so here is one just in case

https://www.amazon.co.uk/PELLET-BAIT-BANDER-TOOL-BANDS/dp/B0075K6GD8
PPS just Bottled my first Batch since about 1980 for a mates upcoming big Birthday and tbh it reminded me of why I bought my first Keg
 
I didnt spot the "not available" but in truth there are loads available everywhere. EBay for one.

Was just surprised a "search" did not find mention of them. Some of the cheaper ones are sprung by a flimsy band like this ....

https://www.ebay.co.uk/itm/Carp-Fis...424477?hash=item3414bff79d:g:A7sAAOSw4vpb45Ai
.... and I guess that if opening the Inlet Seal Rubber (much stronger) the flimsy band would break. I have one though and it still works - so I just never replace the band. All you "lose" is it returning to "home" position as shown in link

The posher ones are sprung loaded internally and are a bit more beefy .... like this a Brand make at a very reasonable rate .... usually around 5 to 6 Pounds and may just do the job ?

https://www.ebay.co.uk/itm/Preston-...528583&hash=item2ab21eb6b6:g:ORwAAOSw4d5bcXat
 
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