I've noticed this year that my 1965 Starcraft aluminum boat has been taking on more water than it used to, so I filled it partway with water and found over a dozen leaking rivets along the bottom. I covered them with tape and once the floor stopped letting in water I discovered that a small amount is also coming in at the sides of the transom. Nothing major, but it makes me wonder if there is a point that I should be concerned with hull integrity, or can I just keep bailing when necessary. Is there somewhere that will rerivet the leakers. Is the transom a big concern since it's just small seam leaks? I'd hate to give up on something just because it's getting old..
Carl...I used to have a 1956 aluminum Lonestar. One of the best boats I ever had.
Here are my thoughts:
1. There's a product called "Gluvit. It's a thin epoxy that you pour over the rivet from the inside. I used it to seal minor rivet leas in the old Lonestar. The link below is from West Marine but it's available all over
2. For major rivet repairs I drilled out the rivet & replaced with a short panhead screw & a self locking nut on the inside of the hull. Then I put Gluvit on that too.
3. I'd be most concerned with the transom leak. Is the transom aluminum covered wood? If it's been leaking for a while the wood might be rotted. The transom has to be the strongest part of the boat since it supports the motor's weight & pushes the boat along from the back. If there's any visible wood, take a screwdriver, pocket knife or awl & jab at the wood to check for rot, delamination or "punky" wood. If it's rotted it's time for a transom rebuild or another boat. In good shape, seal up the leak & look at how that area can be supported. The transom goes thru a lot of flexing so it might be cracked, loosen or weak from all those musky seasons.
That's my 2 pennies,
The transom is a concern, and if the leaking rivets are mostly in the same area, or along a common seam, I'd be starting to keep my eyes open for a newer boat. I got rid of my 1977 Starcraft when it started to take in excess of a gallon an hour.
I was bailing about 10 gallons every 2-3 hours, but the tape has slowed it to a trickle that comes in at both bottom corners of the transom. Thought about drilling out the old rivets and figured that wouldn’t be worth it. Don’t pop rivets have a hole in the middle? I replaced the wood portion of the transom around 10 yrs ago and it still seems solid.
Some pop rivets have a hole & some don't. The ones that don't do so because the ball at the end of the shaft is captured by the rivet. When the shaft is pulled it breaks off & leaves the ball end in the rivet. Prob is that if the ball falls out then you've got a hole. Just a thought but if you filled the hole with epoxy then the ball end might not fall out.
Like I said I used to repair with a pan head bolt, caulk around the bolt & use a locknut & washer on the inside of the boat. I figured the shape of the screw head would disturb the flow of water too much
That is why pop rivets aren't used for a boat hull. Only for above water structure such as gunwales and floors. The rivets they use for the hull takes two people to install. One to operate the pneumatic hammer and the other to back up the other side of the rivet with a heavy steel tool for that purpose. I believe those rivets also have seal built into the shaft and/or under the head and are made of harder aluminum than pop rivets. It takes an experienced boat mechanic to do it right and they also must use the right size rivet for the job or it will not hold or seal properly.