Tried that cheap epoxy putty from Harbor Freight on a thru-hull leak and it did nothing

I had a slow drip around a bronze thru-hull fitting on my 1978 Pearson 26 and figured I'd try the $4 epoxy stick instead of hauling out. After three hours of drying time, the water was still seeping through and the putty just crumbled off when I touched it. Learned the hard way that you really need to dry the area completely and probably use Marine-Tex or just pull the boat. Has anyone else had luck with those emergency putties or am I just using them wrong?

2 comments

2 Comments

james66116d ago

Man that's rough, I feel your pain. I had a similar situation on my old Ericson where a packing nut started leaking bad and I tried that same grey Harbor Freight putty as a band-aid. It just peeled right off like cheap clay, didn't bond at all even when I thought I had the surface dry. I ended up using a two-part marine epoxy that cost like 15 bucks and had to hold a rag over it for 20 minutes while it set up. Those emergency sticks might work for a dry crack in a plastic bucket but on a wet bronze fitting under the waterline they're basically useless.

emmafisher16d ago

Yeah exactly, that Harbor Freight stuff is garbage for anything below the waterline. I tried it once on a drippy thru-hull on my old Pearson and it just slid off like wet soap. It doesn't have any real bonding agents for metal that's constantly wet. The two-part marine epoxy route is the way to go. I used JB WaterWeld on a packing nut once and it actually held for a whole season before I could haul out and replace the nut. You have to really scuff the bronze up with 80 grit and get it bone dry first though. Even then, you're basically buying time until you can do a proper fix. Those putty sticks are fine for a cracked garden hose fitting on dry land but that's about it.