Re: New Silverline owner
Take the drain plug out, clean the brass sleeve with steel wool. Buy a new drain plug or clean the rubber thoroughly. Also, if the drainplug sleeve is loose, water will leak around it. If it is a screw in drain plug, check the threads, any damage will result in a leak. Another thing to check is the mounting bolts for the outboard, water can come through the lower bolts if they were not sealed correctly. This is a serious issue as transom rot can develop. Just look at the bolts from the inside while the boat is in the water to make sure no water is weeping through. Carefully inspect the bottom, especially if there are any repairs from a previous owner. I had a leak through a Marine Tex repair a previous owner did on my boat. Just a pinhole was enough to allow a gallon a day of water. I fixed that repair and have not had a drop leak in since, and I keep my boat in the water for the entire season.
Another possible route of entry is in the splashwell, if water is being kicked up in a wierd way and making it through one of the holes in the splashwell for the throttle/shift cables of the motor. Another, though less likely route of water is through the rubrail. that is an easy test, just spray the rubrail with a hose and see if water gets in. You might just need to let someone drive while you check things out.
Lastly, install a good bilgepump. Good luck....