Solving the Leaky Mast Problem Once and for All!

Winterlude had an ongoing persistent leak where the mast went through the deck.   It wasn’t a big leak, just a nagging pain. The prior owner’s solution was to keep layering stuff on stuff.   Peeling away layer after layer, we discovered every mast boot tape known to the marine industry, mixed with good ole duck tape and even waterproof first aid tape!  When one thing didn’t work, he just layered it over with the next solution of the day!

One winter, we decided we were going to end the mast leak once and for all.  Anchored in French Cay Harbor in Roatan, we were on deck determinedly removing sticky layers one after another with what seemed like miles of cut away stuff that once wrapped our mast boot.  A cruising acquaintance came flying by in his dinghy asking “what are you doing?” — as if it wasn’t fairly obvious.   We’re not exactly overly gracious in chit-chatting with him until he happens to say the magic words.  “Want to know how to solve that leak once and for all, guaranteed?”.  OK, we’re suckers, what was the magic solution?  (and how much was THIS going to cost???)

………….Drum Roll ………….Drum Roll……………..Drum Roll………………

Toilet Wax Ring

Toilet Wax Ring

Seal it with a wax ring commonly used to seal a home toilet to the floor.   We both looked at each other and at the expensive mast boot material we had already purchased on the recommendation of other cruisers and shook our heads … can’t be.  Our cruising acquaintance hanging onto our cap rail acted as if he had imparted the wisdom of the ages and then zoomed happily on his way.    OK, what to do.  Rain is forecast in a few days, we had a sticky mountain of previously used crap laying all over our deck.

Do we put the new stuff in place, or do we see if we can find a toilet wax ring in French Harbor, Roatan.  French Harbor isn’t large, but it does have homes and some of them even have indoor plumbing, so we went to town to wander thru the dusty shelves lining the hardware stores.   Sure enough, the first hardware store with plumbing supplies, had a wax ring for a few dollars.   We bought it.

Back aboard, of course, in the tropical heat, removing it from the packaging was a sticky gooey mess, thank goodness it resided in it’s own plastic tray, designed to contain the goo.   Looking at the ring and the mast step, now cleaned out and exposed, David decided the only way to tackle this mess was to be messier!  So he started forcing the toilet wax ring around the mast … in chunks, obviously since it didn’t fit exactly.  Ooey gooey described this step perfectly.  We were just hoping we’d never have to REMOVE this mess!  One advantage of the wax being so gooey was that it formed exactly to the shape around the mast and the metal ring surrounding it.

Once the gooey part was done, we needed a major cleanup … more on David than the boat.  But finally he was goo free.   We decided to use the nice white mast boot stuff we had previously brought back with us to the boat from the US to cover the toilet wax goo.  We carefully read the instructions and applied the white mast boot over the wax.     It looked good, but we’d have to wait a few days to see if it was leak free.

Two days later a norther/trough parked itself on French Cay Harbor.   Who knows how much rain we got, but we had to bail the dinghy a couple of times, usually a sign of a torrential downpour!   When we removed the teak paneling down below to view the mast as it goes down to the keel, we found DRY!   No drips, no weeping, no puddles, nothing!   So far so good!

Five years later, we have never touched the mast boot and it’s never leaked.  David’s theory, stolen from Eileen Quinn’s song,  is “if it ain’t broke, don’t use it” has been working well.




  1. Friends told us of another use for a toilet ring — never had to use it, but we did carry one after hearing this:

    If you have a major leak around your prop shaft, dive overboard and push the wax ring around the shaft. It’ll seal it up, and you’ll still be able to motor to get to a place to haul and do a more long-term fix.

    Hope you never have to use it, but . . .


  2. Hey Jan and David!
    We were just stuck in Fernandina for 4 days with torrential rain and winds. We’re pretty sure our mast has been leaking for awhile and water seems to run along the headliner and then spring a leak in a few different places. We will def try this as soon as we get back to Brunswick to check on her. Thanks so much! Enjoyed meeting you in Marathon!
    Have a great summer.
    s/v Seeker

    • Hi Kathy! Great meeting you guys in Marathon! I hope the toilet bowl wax ring works as well for Seeker as it did for Winterlude — it’s been years now and (knock on teak) we still don’t have any mast leaks! I probably just jinxed us. Hopefully we’ll see you next winter! Cheers! Jan


  1. […] led me to Commuter Cruiser blog post where they used an interesting way to seal their mast leak. A toilet wax […]

Speak Your Mind