Trooper Problems, Help

A friends son has an Issuzu Trooper with problems;
There are apparently three lines that come off the top of this fuel pump which are connected to various locations.There is a fourth rubber hose that is connected to the bottom of the fuel pump which is not hooked up to anything and is dripping gas. This is a carburetor engine and the question is : is that bottom hose and external vent or should it be hooked up to something and if so to what?The fuel pump is a mechanical lift type off the side of the block.
see the attachment...where does this hose go?

Not having experience with a Trooper....but with many other cars...
most mechanical pumps for carb engines have 2 lines - one to tank, one to carb. inside the pump is a rubber diaphragm that when moved by the engine running pumps the gas.
IF this diphragm has a hole in it, the breather hole will leak gas...so you need a new pump.

Now, as to the 4 lines you say you have...
the only pumps i have seen with 4 lines are those that are helf fuel pump, half vacuum pump. (cars from the 50s have this as they have vac operated wipers, power locks, ect)

You say you are having problems...what problems?

As it turns out, the 4th hose on the opposite side of the fuel pump from the other 3 is an overflow. It is there so when the diaphram goes on the fuel pump, it runs the excess fuel down the hose and away from the engine. Replaced the pump and no more dripping.
This is "rice technology".
Thanks for the responses.