rear lift eye loading

The lift rings on ALL correct crafts are designed to carry verticle loads equaling about half the weight of the boat. With that said, I have used the rear ring for years to pull tubers without any problems or signs of stress.

In order to better evaluate the lift rings suitability for purposes other than lifting the boat, you should know the following:

1. The lift ring is attached to a threaded rod which in turn is attached to a steel angle (or similiar depending on rear). This angle is anchored (glassed in) to the transom. The method of attachment to the transoms depends on year of the boat.
2. The two exposed screws on the flange of the lift ring is only designed to keep the lift ring from rotating or moving slightly laterally on the deck.
3. The deck around the lift ring is support by plywood blocks via a nut on the threaded rods. This prevents the deck from flexing downward and producing an unsightly gap (and striping screws) at the base of the lift ring.

So, as you can tell by the above, the ONLY thing that allows the lift ring to handle lateral loads is the thickness of the fiberglass deck resisting the sideways load on the base of the lifting ring (the portion of the lifting ring that penetrates the deck. Therefore, it is possible that a significant lateral load can tear or crush the fiberglass deck resulting in failure.

With all the above said, the least you should do if you insist on using the lift ring is to reinforce the fiberglass deck from below by laminating additional fiberglass fabric to the bottom side of the deck around the lifting ring. Even consider glassing in an aluminum plate to distribute the lateral load across a much wider area. Take this for what it is worth.