Radiator valve drain washer ?

[tonyb61]

My radiators downstairs all have drain points so I can empty and remove them when decorating etc. They are slightly unusual. The radiator tail has a small drain outlet with a threaded end fitted with a small cap with a rubber washer/disc in the bottom. To drain the rad, you unscrew the cap. Usually the rubber washer/disc is usually stuck over the end of the drain outlet and you have to prise it off.
However the last one I did the disc was so perished it fell apart when I did that. I have not been able to find a replacement anywhere. It is a solid rubber disc, about 6-8mm diameter. Is there anywhere I can buy this ?

 

[Best]

You could try the wee washers for standard old type high pressure ballvalves. They are probably about 10mm in diameter, I guess & are fairly thick - about 3mm or so. You could always trim them around their circumference with a sharp knife if too wide.

 

[lame plumber]

washer kit at merchants