Hello Alan,
you didn't say what you were making but with end grain tear out I assume you are hollowing. First thing is to make sure that the tools you are using are the right tools for that particular job, make sure that they are sharp, do not be afraid to sharpen at the least hint of bluntness. Sometimes even with sharp tools you will get tear out so try a sheer cut. If that doesn't work try soaking the area to be cut in sanding sealer and trying again once it has dried out. You may want to re-assess your lathe speed and cutting speed(of the chisel)
I hope this helps and I'm sure there will be more advice posted as the evening rolls on.
Regards
John BHT