went 4 a short spin in my disco bout 4miles i wud say an when i stopped i heard a hissing at the front so i opened the bonnet up an round where the brass plug is on the raditor well it appeared to be coming from there i could here a hissing sound when i got home i checked the oil an its ok no creamy stuff just normal looking oil so could it b possible the rubber seal round this brass plug is knackered if so is it a hard job to do i.e will it b seized in its hole requiring a lot off work to get it out? hope that explains it hope to have some answers soon ty

 

And there was no coolant visible where the hissing sound was coming from? Have you checked your coolant level?

 

no coolant is leakin just the hissin sound round the brass plug sayin that the coolant lvl was a bit low but no coolant under the disco b4 i set off or wen i stopped i have a habit off always checkin underneath wen i park up or move off an as far as i am aware no coolant has escaped

 

Well let it cool off and check it!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

Definitely make sure you've got enough coolant in there. If air is escaping, coolant can escape. And if the level is low, then it's obviously gone SOMEwhere.
The concern is that you have something suddenly leaking from a pressurized system that wasn't leaking before. Make very certain that your system is not evacuating the coolant, and try and make sure you find exactly where the leak is coming from. You definitely don't want it to suddenly blow out on you.

Worst case is that it's getting over pressurized for one reason or another(bad head gasket or other overheating), and something is beginning to crack. Or the radiator is just starting to crack somewhere because it's old.
Best case is you just need to give that brass plug a 1/4 turn, or tighten one of those hose clamps that go into the radiator right near that plug.

 

okey dokey checked it wen it was cold still no leak will take it the garage see whats what with it chers 4 the replys

 

Remove that plug, make sure the rubber gasket is still there, put the plug back.
Takes all of 5 min and that includes opening the hood.

 

The plug on my first radiator was plastic, and I don't think it had a gasket. The plug on my current radiator is just a metal (not brass) plug with a square head, no flange and no gasket. Just a straight ol' plumbing plug. It does seep just a tiny bit, though.

 

yip it was the washer round the brass plug sorted now on a plus side i waxoiled the underneath cost me 100plus pounds 3gallons plus thinners shall give it a another coat in august thanks 4 the repleys etc