IF,,, you can verify the EXACT location of the leak, AND it is a pin hole instead of a crack, you can fix it with a drill and epoxy like JB Weld. Just clean the area (on the inside) very well with alcohol or white vinegar, lightly sand around the area on the inside, drill a small hole (approximately 1/8"), cover the hole with duct tape or masking tape from the outside, the fill the hole (make sure it is completely worked ALL THE WAY into the hole) and coat the area around the hole (maybe 1" diameter) with epoxy. You can leave the tape off the outside if you don't mind the repair being a little messy and the epoxy thick enough that it doesn't run through. You MIGHT be able to fix a small crack the same way, but drill a hole centered at each end of the crack, this will stop the crack from "running". Then apply epoxy out to about 1/2" on each side of the crack and 1/2" past the ends. There are several flexible marine grade sealants on the market which might also work, as well or better than, JB Weld.

Another solution for a pin hole that is UGLY but almost always successful, is to drill a hole just big enough for a Stainless Steel machine screw. Coat a SS flat washer LIBERALLY on both sides with silicone sealant, put on the screw, put the screw in the hole (from the outside), coat another SS flat washer and put on the screw inside, then install the nut and snug things up.

Good Luck

Pappy