PCV system problems

My engine makes a hissing noise, and the tube connected to the pcv valve is wet, so i guess it's time to change the valve, since it's old and probably dirty, it's cheap so why not do it.
Apart from that, is there any way to avoid using a valve? i already have a hose connected to the pipe that fed the induction with oil vapours, so that should mean the intake valves won't get any filthier, right?
Can anybody explain how that system works on the jimny?

They all work pretty much the same way.  The valve closes when manifold vacuum is high, e.g. at idle or on the overrun, since the engine is unable to burn crankcase gases under such conditions.  On the overrun it certainly can't burn them, since no combustion is taking place in the cylinders.

If the valve sticks open or is removed, you will get a lumpy idle or stalling, and nasty emissions on the overrun.

In t'olden days there was just a vent tube, via an oil catch can, from the crankcase to atmosphere, preferably at a point under the car that got good airflow.  Apart from working less well at low road speeds (at high speeds the airflow gave a sucking effect), it turned out that crankcase gases were a major source of local pollution.

Ok, so I'll have to replace the valve.
I have a hose connected to the front of the valve cover (in place of the pipe connected to the intake tube) and going to the ground to use the air as suction as you said, would that damage the engine in any way?
Also should I leave the pcv system as is or should I install a catch can as you said?

It could potentially allow water or dirt in, as well as failing an MoT if the tester sees it.  I would stick with the original design.

i could do that but i have replaced the intake tube and the new one doesn't have the opening to which i can connect the old hose, and for now the pipe has always been clean and no water or dirt have entered, but i could put a small cone filter on it to avoid that possibility altogether. wouldn't that pipe be pushing out gases though?