Is there anything i can use,instead of cork.I need a new sump gasket but don't want to use cork.
Thanks 
james

On what motor?
If its a pinto or Kent then no.  There is nothing wrong with cork gaskets!  the problem most often is either (or both) of 2 things:
1. the sump surface isnt flat around the bolt holes
2. the person fitting the gasket covers the thing in silicon.
 
They only need a dab of silicon in the corners where the cork meets the rubber things.
 
Later model engines will use a paper gasket or in some cases nothing at all but that is usually when both the block and sump are alloy not pressed tin against cast iron.

Gdub
On what motor?
If its a pinto or Kent then no.  There is nothing wrong with cork gaskets!  the problem most often is either (or both) of 2 things:
1. the sump surface isnt flat around the bolt holes
2. the person fitting the gasket covers the thing in silicon.
 
They only need a dab of silicon in the corners where the cork meets the rubber things.
 
Later model engines will use a paper gasket or in some cases nothing at all but that is usually when both the block and sump are alloy not pressed tin against cast iron.

agree with the above but would also add
3. over tightening.
cheers

All of the above for sure, plus I'd also recommend checking that the oil pump isn't fouling on the sump & the edge of the oil pick-up mounting flange isn't caught between sump & engine block.
That was the main source of my sump oil leaks, bit of grinding/filing & all's good . . . hasn't leaked a drop of oil in six years now.
 
Cheers, Jason.