1986 Jaguar XJS engine running rich

I've installed an used motor from florida. And when I started it ran rough and was emitting black smoke out of the exhaust. After it runs for a short time, it begins to load up and will die when you try to use the throttle. It will not start after it dies. Atfter a while it will start again, but it will do the same thing again as mentioned above. This is my first Jag. XGS. I had someone bring in a 86 Jag. To use as a guide for wiring and vaccum hoses, but there is some slight differences in the two cars. One is a XJSC whike mine is a XJS. Can you help me?