im looking at buying a 16ft aluminum boat from a co-worker and it has a little leak.he said that it leaks about half a gallon or little less in a eight hour day with 2 peaople in it.is there something that i can use to seal the leak or something that i can do to stop the leak.

There are, and what depends on the source. If you have a loose rivet you could drill it out and replace it. There are also numerous product to put on it. I have used JB-Weld, HTS-2000 brazing rods (work real well), and I have had to call a welder for a crack I had right on a seam on the bottom of the transom.

One warning on the JB-Weld the welder had me go back and remove every trace of it before he would touch my boat.

I have seen folks here use various epoxies, and other items to seam cracks. Depends on how big the hole is, and where it is.

I think a half gal a day is normal

J B Weld

If it is a rivet and you can get to both ends, just get some help and whack it with a hammer while the other person holds a hammer against the other end. If it still leaks, you can do what the others suggest.

No leak is normal.