Ajr897 wrote:Q1: is the interior foam “wrecked”?
Whenever a Unibond hull is in the water and there are open holes in the hull below the waterline, water will be able to get into the interior of the hull if the holes are deep enough to expose the foam. Once the foam gets wet, it can be hard to dry out. That is especially a problem if the foam is saturated with water and the temperature drops well below freezing. The water expands into ice and causes more damage to the foam. Foam that has not been busted into larger cells by freezing should not continually suck up more water if it just got wet on the exposed surface.
The holes in this 15-footer should not have had too much water forced into them when operating on plane. The flow of water at a right angle to an open hole on the hull bottom will tend to keep the water running past the hole, due to the Bernoulli effect. In theory, it should tend to pull out any water that was in the hole opening, aided by gravity, too.
Assuming the boat has been on the trailer for a long time--many months--and assuming that you do not see water dripping out of any of the old screw fastener holes, then your situation is this: whatever water got into in the foam and was going to come out the same way it went in has already happened. If water moved through the foam to some other place lower in the hull, it won’t intrinsically flow uphill to get out of the hull. You could let the boat sit for ten years and the foam would not get appreciably less wet than it is now.
The hull was already going to be heavier than a 15-foot recreational hull, so weighing the hull as means to see how much water might be in the foam is not going to be a very useful method of analysis, unless by some chance you have an actual factory weight for the hull with the amount of gear and added weights that normally would be in place when the boat was built.
Usually boats from the Commercial and Government Products of Boston Whaler (or the subsequent entity Brunswick Commercial and Government Products) were all built to custom specifications, and finding exactly what the original weight might have been specified by the factory is going to be difficult.
Since you are buying from a family member, I would assume you will get a favorable price. I would assess the boat as you suggested, that is:
- tape over all the holes below the water line,
- put boat in the water,
- see how hull sits on its lines--here you need to have an engine and other rigging on the hull to really see how it is going to sit--and,
- see if the (unspecified engine year, model, and horsepower) can easily put the boat onto plane with just you and minimal gear aboard.
A good gauge of proper static waterline is the position of the engine splash well drains relative to the waterline. The drain opening on the outer face of the transom should be just above the water line. If the drain opening is partially submerged, that is okay. If the drain is completely below the waterline, that’s not the proper position, and there is too much weight in the stern of the boat