I have a pipe on the kitchen sink that is leaking as shown in the picture below:
Would it be enough to just tighten the bold from where the leak starts (in which case I need to buy a pipe wrench) or call a plumber to replace the brass pipe which look to be rusted on top?
It appears to be leaking at the compression fitting from brass or copper to ABS. Simply tightening the nut there should do, but you may need to disassemble and clean off any calcium deposits to get a good seal. A ChannelLock type plier works well.
The reason it's leaking, though, is probably because the trap is clogged. You wouldn't normally have enough back-pressure to push water out at that point. If the trap is constructed with similar compression fittings, simply take it a part and clean things out. The clog is probably grease and soap goo.
