1979 MONTAUK 17 Rigging Tunnel Repair

[PopeyeSJI]

I am overhauling a derelict 1979 MONTAUK 17. I have found the hull scarred but not waterlogged. Whereas I am able to repair the surfaces and drain-tube holes to prevent future water-incursion, I am struggling for solutions on how to seal and renew the rigging tunnel that runs under the deck from the console to the stern,
.

The rigging tunnel appears to have once had an aluminum tube inserted, which has now deteriorated and exposes the fiberglass glass to possible water.

Fig.1. The decayed rigging tunnel.

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Fig.2. The aft end of the rogging tunnel.

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I was thinking to try to insert a PVC pipe and seal the ends.

Please suggest a better solution.

[Jefecinco]

Perhaps a new tunnel could be used by installing a new piece of PEXpiping pushed through to the console.

[Phil T]

Installing a smaller diameter pipe and sealing the ends is a good approach.

[o8er]

[After about one year of no new replies]

Q1: could CIPP lining, which plumbers use to re-line plumbing pipes, be used to re-line a rigging tunnel?

[o8er]

Q2: what are your comments about this plan:

• Use 2-inch-diameter flex or three 1-inch-diameter flex or whatever will fit
• run [the rigging] above above the console floor
• seal the console deck hole around the flex
• nothing can enter the hole
• repeat at the other end.

[jimh]

Q2: what are your comments about this plan:

What is "flex"? Please give a link to details about "flex" so readers will be able to better understand your plan.

Also, I don’t recommend completely sealing the aft end of the rigging tunnel. Water will inevitably get in the rigging tunnel, and there should be a way for it to flow out into the sump area.

Crazy Idea
Here is an idea for restoring the rigging tunnel: use a hole saw to clean up the existing tunnel.

The method of drilling a rigging tunnel with a hole saw was mentioned many years ago by contributor Steve F, who I think was a very crafty and skilled fellow. He used a hole saw to actually create a rigging tunnel in a Unibond hull which had none, a SPORT 15. His method was very unusual.

The method requires that there be a hole in the transom that is aligned with the center of the rigging tunnel. An extension bit is passed through the hole, and the hole saw is then attached to the inboard end. An electric drill is attached to the outboard end. The hole saw is aligned with the rigging tunnel and begins cutting--in this case it cleans up the existing rigging tunnel to a more uniform diameter. When the hole saw goes as far as it can with the first extension bit, a second extension bit is added, and the cutting resumes. This is repeated until the hole saw cuts all the way to the center console end of the rigging tunnel.

If done carefully, it should be possible to rework the existing rigging tunnel into a uniform diameter. At that point you should be able to pull into the rigging tunnel some sort of flexible plastic tubing or hose. The hose could be trimmed flush at each end of the tunnel and sealed in place.

As for the necessary hole in the transom that perfectly aligns with the rigging tunnel, you may have to create that hole. Depending on the static trim of your hull, the hole in the transom may be above the static water line, and if so, it just can remain as a engine splash well drain, installed with the usual brass tubing and rolled-over ends.

If the hole is below the static waterline, then you just plug the hole with a wooden bung, epoxy resin, and if desired, gel coat resin top coat.

Steve F. actually did this when he modified his SPORT 15 into a CENTER CONSOLE 15. As I mentioned, Steve is a very skilled at this sort of work. Here is an old thread that includes multiple links that give more details:

Convert a 15 SPORT to a CENTER CONSOLE
https://continuouswave.com/ubb/Forum1/HTML/009523.html

Another approach to rigging tunnel restoration
Another way to restore the rigging tunnel is to just turn it into a long trench through the cockpit. You will have to cut out the deck above the rigging tunnel, removed the foam, and create a new open trench into the hull. This will be quite a bit of work and will need skill in laminating a new covering of fiberglass onto the foam. When the trench is done, then you can use the cut-out section of the deck as the cover, again probably needing some skill with fiberglass to turn that cut-out deck into something more aesthetically pleasing and functional.

To see such a modification visit this old thread:
1986 15 Sport Restoration and Conversion to Center Console
https://continuouswave.com/ubb/Forum1/HTML/022657.html

The photo pages are still on line at

https://15whaler.wordpress.com/

There are many, many photographs. Keep scrolling until you find the ones that show the new trench cut out made into the hull. There is no reason you couldn’t use this approach on your older MONTAUK 17.