Hobie 16 mast base

Hello, I'm new here and a new Hobie 16 owner (I believe it's a 1982? The serial number and date are scratched into the stern of the starboard pontoon).

I'm not really new to sailing, but it's been a little while. Anyway my first question is about the mast base: Should it be somewhat loose in the mast? Both rivets are still present, but I can pull it out about 1/2" or so it looks like before it stops. Will this allow water into the mast in the event of a capsize? What is the proper fix?

Thank you! Lots of great information on here.

The mast base should be firmly attached. On the H16 the mast base controls mast rotation, so a loose mast base can cause wear at the interface and other issues. The primary water seal is a foam plug just above the mast base, although having a sealed mast base is nice.

I recommend removing the mast base and inspecting the rivet holes. Generally you can just recaulk with silicone and install new rivets in the old holes. If the holes are a little oversized a rivet sleeve may make the difference. If the holes are really bad drill a couple of new holes and put 4 rivets in.

Thanks for the reply. I'm sure the info can be found somewhere, but any idea what size rivets one might use?

This is very dangerous when stepping the mast. Very little issue when sailing.

https://media.hobie.com/digital_assets/14-16_March_2017.pdf#page=2

Base 8010131 RIVET POP 3/16x3/8 PH-SS

Replace and add two more.

_________________
Matt Miller
Former - Director of Parts and Accessory Sales
Warranty and Technical Support
Hobie Cat USA
(Retired 11/7/2022)

Thank you for the excellent help!

I'll have other questions, but I'll deal with this problem first before resurfacing...

Before you embark on this first project check your mast for leaks. Now is a good time to make sure everything is sealed up.

What is the best procedure for checking for leaks? I don't have a pool or anything large enough to submerge the mast in really (except the lake, haha)

The lake.

Ideally do this with 2 people, one on each end. Lay it flat on the water, it will float. Push it all the way under. Then push the mast base a little deeper, look for bubbles at the head of the mast. Then push the head deeper and look for bubbles at the base. Keeping the mast under water check for bubbles along the length. The tang may leak, or perhaps a cleat. Lift the mast out of the water and tilt it back and forth. Listen for a slooooooooooooooooooooooooosh. If you hear water running along the length of the mast, you have a leak between the mast head and the mast base. It may be the foam plugs, or more likely it is the rivets holding the tang, cheek block, or cleats. Set it some place to dry. If there is water in it tilt it towards the end you suspect the leak is on. If you were correct the water will slowly leak out, especially if the mast is warming up.