Exhaust gases waterlock

We had no intention of disassembling the waterlocker too. However, a major inspection was due, and I opened it. The locker consists of two stainless steel lids at both ends of a big rubber hose for water in and outlet. Lately, inside the boat, it smelled of exhaust gases. It turned out corroded stainless steel was the reason, tiny little holes. It took me a good hour of welding all the holes, which seemed to get more and more the longer I worked. Eventually, all was fine, new painted and assembled. The smell has gone, thank God.