[Rick Parkington]

In my experience, brass taps become very stiff and sometimes need pliers to operate them! Maybe I have been unlucky but I still prefer cork taps. I find leaky corks are usually withered away and so cannot be saved, probably depends how bad they are but boiling water is definitely the answer for fitting new ones, it makes the cork very spongy and pliable. I have seen corks for sale for Ewarts 'pull on/push off' taps that are made from cork rubber (as used for old car rocker cover gaskets), trouble is they are the same thickness as the worn out corks, so I doubt they're much good. The proper corks are made from natural cork (like a wine bottle, not made up from bits bonded together) and should be twice as thick as the old ones. They won't fit unless they are soaked in boiling water which of course creates the tight fit that makes a good seal. 
Cheers Rick

[VicYouel]

Boiling them has always worked for me every few years!
Vic

[Greybeard]

I have heard that boiling the cork for a while can refresh them, though Id suspect it will be just a temporary measure. The quality of replacement corks is variable though as John describes they are straightforward enough to swap.
I tend to fit complete replacement taps when the time comes nowadays, though not the repro ones that are generally not very good.
The ones I like that do not look out of place are the brass lever types. Pricey, but reliable.
This the sort of thing - I imagine they can be found cheaper elsewhere
Sorry about the long link 
http://www.gsparkplug.com/gs73083-petrol-tap-universal-round-brass-lever-type-with-filter-1-8-x-1-4.html?gclid=Cj0KCQjw5LbWBRDCARIsALAbcOflXBVNOYpi0OJYzJ4fRLcSe3Uj5unqMayCABozNdBVPvdCUdxJWjsaAtBVEALw_wcB

Steve

[singleminded]

If the tap has not been used for a long time you could soak the corks in water to expand them.
To remove the corks you have to push the pin that projects through the knurled end ring out(in the direction of the cork). Sometimes you have to file the pip off and there may not be enough left to rivet it back in place. I hope that makes some sense to you..John

[Thomas]

Hi all, my fuel tap leaks. Attached is a picture of the tap with the built-in component. I assume that the gasket is out of cork and I wonder how to solve this problem. How can I detach the cork? Is there an alternative solution?
Cheers, Thomas