How to tell if hollow stringers are bad? 20' 1969

[69Seacraft20]

Well that's good news! I have no real reason to suspect anything is wrong with it...just old boat anxiety. Transom looks and sounds rock solid even with 526lbs hanging off of it but deck will need to be redone eventually. I'm not sure if I have to pull the liner out or cut to replace deck. That link "this article" did not work.

Thanks!

[flyingfrizzle]

My 71 had the quad stringers. They didn't have foam in them but did have foam between them in the voids. The earlier 4 stringer grid stringers are far stronger than most boats and with no wood there is no rot. Only worries are if there are any cracks along the 90 degree areas where they have flexed. The only ones I seen damaged were from extreme beatings and that was on the large box stringers not the quads. If you find wet foam anywhere, get it gone look for stressed areas (you will more than likely not find any) and worry about the deck balsa and the fir in the transom if original. That is the only areas that normally have issues. Some hulls have rotted wood in the caps if lots of holes were drilled in them but the older 69-72's had super thick cap layups so may be ok there. The awesome stringer set up in these hulls are what makes them so good for rebuilds, I is one thing less to redo.

[Bushwacker]

Originally Posted by 69Seacraft20

. . . Transom looks and sounds rock solid even with 526lbs hanging off of it but deck will need to be redone eventually. I'm not sure if I have to pull the liner out or cut to replace deck. That link "this article" did not work.

Thanks!

Since that boat was designed to have about 300 lbs hanging on the transom, I hope you've moved batteries and console forward to get the CG back where it's supposed to be! Otherwise it's not balanced right, so ride and min planing speed won't match the original.

If you ever have to redo the deck, you can just cut through the top skin, scrape out the rotted wood and replace the core, which is mostly balsa core with some plywood where seat pedestals were mounted. However if you don't drill holes in it, or seal any holes with epoxy, there is no reason for the deck to ever deteriorate. My boat is all original except for the filled in transom and everything is still solid; if fact, when Don Herman filled in the transom, he said it was the driest transom he had ever seen in a boat that old! I did address two potential "transom killer" areas when I bought my 3 year old boat:

1. Frank Brown, Moesly's mechanic on his race boats who sold me the boat, said the polyester putty that was used to seal the top of transom when they dropped the cap on, was very brittle and would crack easily. Frank said that before installing a motor on a new boat, Brown & Hauptner Marine always removed the aluminum trim from around the motor cutout, routed out that joint, and caulked it with polysulfide sealant that would remain flexible and keep water out of that joint. Since I bought the boat with no motor, I did the same thing before installing the motor.

2. If you have the live well under the port seat, the plastic cup in the transom at the waterline which functions as the water inlet/outlet, is also sealed with polyester putty which will also crack and start to leak, as mine had started to do. I removed it, dried out the wood with some alcohol, treated it with Git Rot, and replaced the plastic fitting with a Pyhe plate and PVC threaded cap, all sealed with epoxy.

That link that didn't work just goes to the '69 Boating Magazine test of the Seafari that's in the literature section. You can get to it by scrolling down to bottom of page and clicking on "Classic SeaCraft Home", and then click on "Literature". Or you can PM me with an email address and I can send you a .pdf file of that article. It contains a very detailed description of the hull and stringer laminate schedule, how the stringers are installed and variations in hull thickness. I tried to attach the file to this post, but at about 2.5 MB, it's too big!