Transom Jobs

[SeaReel]

My dad turned me on to the site a couple of days ago and instead of doing research I have been surfing your site. We own a '77 25 ft and a '75 17 angler. They are great fishing machines and I grew up working on the 25. We have had it since 1981.

It seems that most restoration jobs involve a lot of work in and around the transom. This is really scary considering the age of our boats. It is my understanding that the glass provides the strength of the hull not really the wood. Are these transom jobs voluntary? If not, how does one determine if it is necessary?

From examining our boats there is evidence of some blisters in the gelcoat in the transom but these come and go. When looking inside the bilge the glass looks like it is in pretty good shape and the stringers are solid. I mean I am not a yacht inspector but I did do fiberglass repair for a couple of years.

Any comments on transom issues please let me know or direct me to previous posts. Thanks,

Cliff Ruehl

[RingLeader]

Welcome to the board. Fiberglass provides strength, but a core provides stiffness and compressive strength. Fiberglass with a weakened core will be flexible and through flexure overtime will crack, fatigue and eventually break out. Its not until the fiberglass becomes delaminated from the core that the majority of stiffness and over-all strength is lost.

I could literally see my transom jolt as the outboard was shifted into gear. I could also see it move up to several millimeters while underway in a choppy sea. Mine wasn't all that rotten either.

Transoms and stringers are two different animals. Transoms are under a great deal of stress from a 500+ lb. motor hanging on it and on top of that exerting who knows how many thousands of pounds of thrust to move the boat through the water. All of this is big time stress on the transom. Motor mount bolts will eventually sink into a soft core and the motor will become loose on the transom.

Stringers are like I beams down the lenght of the boat. Most of the time the wood in the stringer is just a form that glass is laid over. If there is sufficient bulk of glass over the wood, then the core is almost non functional. Its when the entire stringer, glass and all, separates from the hull that the problems begin. Some manufactures build hulls with hollow or foam filled stringers. But you'll notice that these stringers are usually wider than the cored stringers.

I'm no expert either, but these are just my opinions. Many of us just feel better knowing that our boat is soild beneath our feet.

[Strick]

A skill that many surveyers use to diagnose a comprimised transom is the tap test. The surveyer will use the blunt end of a medium sized screwdriver and tap it on the transom from the outside. They are listening for differences in the sound of the thud that may signify moisture in the core. Infact they will also tap the entire hull looking for soft spots.

You can use a moisture meter to detect water in the transom however I've heard that they can be unreliable.

Some people will grab the outboard motor and pull down on it when the boat is on the trailer. If your transom is weak then you may see some flex while you are pulling down on the motor.

Probably the best method to diagnose a wet transom is the most invasive method and that is to drill some 1/8 inch holes in multiple areas of the transom looking for moisture in the wood that comes out with the bit. Of course you will have to fill the holes when you are finished unless you find lots of moisture then you may as well leave the holes because you will have lots of work ahead of you []

The transom is the heart of the boat and most of us feel safer knowing that we re-built it stronger then when it rolled off the factory floor

Strick

[warthog5]

Quote:

Some people will grab the outboard motor and pull down on it when the boat is on the trailer. If your transom is weak then you may see some flex while you are pulling down on the motor.

This is done with the motor tilted and lock in the up position. It gives a lot of leverage.

[SeaReel]

Thanks for all of the replies. They were very helpful. We will try some of your ideas. I think both boats suffer some water damage where the swim platforms are but I don't think either boat has delamination problems.

Tight lines,

Cliff