I have a 1980 Civic. My brother got it for me and we have tried to fix it. The guy who had it before pretty much ran it into the ground.
We had to change the carb, but since it didn't start like my brother and friend were hoping, I'm 99 percent sure that they may have messed with it.

Now as soon as you start it there it TONS of white smoke flooding out of the engine area. It used to come from under the car as well, but I had the exhaust system fixed and it doesn't come from there anymore.

I think that it could be a blown head gasket... I have no idea how to change it.