WD8 Restoration, help please

Hi my first restoration project is a Wolseley WD8. Got her up and running today, very very pleased but I notice she is leaking water from the head gasket. It's a new gasket (copper) and the head bolts are on really tight. Someone has suggested using some sealer around the gasket but am a little concerned. Is this usual practise? If it is can anyone advise the best sealer to use?
many thanks
Julie

I had that with my lister d, firstly clean the two sides super well, no old gasket, carbon, dirt ect. if that still doesn't do it (which it didn't for me) I used red Hylomar. I'm not sure if you can still get it, but it works a treat.
I don't think its the usual practise but needs must!
I have seen people using fibre gaskets without the copper part before, is suppose it would mould around any imperfections better, you must make sure its the same thickness though (it will adjust the compression ratio).
hope this helps,
Callum

As Callum says get both surfaces very clean. You might want to check it's flat using a straight edge and see if there's light between the head/block and straight edge or use a thin feeler gauge. If you use a sealer please don't use a lot when you tighten the head down it could squeeze into the bore and stick up the piston rings. Sealer on head gaskets is a very last resort!!!!!