jx sump plug

[mrdp]

Hi All,
Just doing an oil change on the 1.6td jx. previous owner had 2 copper washers and some kin of cement gum on the threads.cleaned up the plug and went to refit only to find without the aid of the gum stuff ( exhust gum maybe?) it doesn't seal. Read that the jx doesn't have washers, so removed them and refited, sometimes it just about does up but weaps tiny amount other times it nearly goes tight but then goes loose again like a coke bottle. I'm guessing the threads aren't all they shoul be or its not the right sump plug (it does have a tapered end-unthreaded part, but i don't think it has a tapered thread. does any one know a good way to seal it ( exhust gum on plug again!!???) am off to france in a few days need a quick fit.Any idea on wether its the wrong plug and where to get a new on brickwerks has one but comes with a washer?? help.