Got a 1973 v8 , haven't used it for several months l drove a few miles to get some fuel , struggles to start it again , then put into Drive and just died , started again ,ticked over fine put into drive and died! Left at the side of the road went back after a few miles and drove it back home a few miles fine , left it running for a few minutes and Same problems again l put into gear ,jumps then dies , any ideas ?????