1988 nissan pulsar wont crank

The black color of the spark plugs indicate that the engine was running rich (too much fuel). The fact that they were wet tells me that there may not have been ignition. The carb being wet may be just from flooding when you tried to start the engine.
First off you need to determine if you are getting spark. You can do this by connecting one of the plugs to a wire and grounding it to the block. Have someone crank the engine and watch the plug for spark. Blue is good yellow is week. Use care holding the plug as it can give off a nasty kick. If you don't have spark than its time to check the wires, distributor cap, rotor and so on.