Rubber-plug causing hull leak? And what's its purpose?

My starboard takes on hardly any water. My port-side takes on a bunch more. I noticed this when I put my Getaway up on the cat trax / beach wheels. Not only did water leave the drain plugs, but also water came out of the translucent-looking rubber plug thingy that's located on the inside of the port-side hull underneath the trampoline. From a birds-eye point of view, the rubber plug thingy is located about midway between the stern and bow.

1. What do I do to fix this leak? Or is this normal?
2. What is the purpose of this rubber thingy. (It's found on both hulls.)

The holes on the inside are for draining the coolers.
there should be a plug inside each cooler if you put ice in there and it melts, you drain it by pulling the plug.
sometimes the circle plate will let water in your hull.
hope that helps.

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Jerry Malone

Thanks for the reply.
I've seen the plugs on the inside of the hatches/coolers.

The plug/hole I'm trying to identify is on the outside of the hull, below the trampoline line, around mid-ship. It's a translucent plug. Is that what you're talking about?

The hole under the tramp is connected to a tube that connects to the cooler drain.

Thanks. So it sounds like it is possible for water to leak into the hull via this tube?
I should probably do a leak test by blowing air in the hull.

I have a similar issue with water entering my starboard side hull only. I spent a lot of time at the end of last season trying to figure out the problem with soap on the seams and blowing air into the drain plug.... to no avail. The cooler drain tube is something that I did not look into. I'm thinking that if the tube is somehow disconnected from the hull drain hole that it may be possible for water to directly enter the hull while sailing. My sailing season is still a couple of months away....so if you figure this out please post.
Tim

If it helps.... I had the same issue and spent time last season blowing air and soaping seams to try and find the source of water. My problem was the cooler drain tube. I was disconnected from the side wall inlet near the cooler. I was able to re-attach and add a ss-hose clamp. Problem solved.....
Tim