I have never even heard of anyone using anything other than vaseline and only ever on the main rubber seal and not the rubber parts of the valve. I probably use about 2 or 3 bulbs on a keg but it depends on temperature and how quickly you drink. You could stock up on them when either Wilko or Tesco Direct have offers or buy in bulk (300/400 bulbs) from Amazon or other suppliers, if you think you will use them.duncan37uk wrote:I've ordered a 2" barrel cap with full 8 gram C02 injection system (with 20 CO2 bulbs). I also ordered some barrel seal grease. Probably no different to vaseline but then it doesn't seem any more expensive either! How many bulbs am I likely to need to use (after sealing and tightening the cap) to get the carbination levels of the barrel up? Should I add some more sugar too?
Sorry, lot of questions!
You will only need one bulb to rescue your current brew. It will be problematic though as they are designed to fill the vacuum, when you have drunk a good part of the keg. With about 36 pint of beer in there, there is not much room for the co2 to expand. Most of it will vent off through the pressure release rubber valve but as you might have guessed, it is not a precision mechanism!! As long as you get enough pressure in there, the beer will carbonate nicely in a couple of days.
You might be able just to put in more priming sugar and not use a bulb. I have never tried that so someone else will have to comment if that will work??? I wouldn't do both though - too much pressure.
If you get on with the bulbs you might find you want a better bulb "holder". If you got the red plastic one, you might find the threads strip before long and they become useless. Fortunately there are part/all metal alternatives. I also find a little bit of vaseline around the narrow neck and barrel of the bulb helps avoid losses.