460 mast step leak

jimali

.
Oct 5, 2009
14
hunter 460 Portsmouth uk
Hi

I have a 460 in the UK which has a leak I am trying (frustratingly) to trace.The boat is out of the water by the way.

I think it is coming in via the mast step and then travelling down inside the compression post exiting at the bottom. I found water there today (see photo) and about a gallon in the bilge - which I had dried out last week. We have had a lot of rain.

I believe the mast compression post is hollow and can see from underneath where it pokes through a hole in the deck presumably to sit under the mast deck plate. I believe the deck plate is solid apart from the bolt holes which are dry on the inside.

I can find no water in the area under the deck hence why I think it must be travelling under the deck plate and then down inside the post. My confusion is how so much water is coming in as I am struggling to find any significant gap at deck level and am a bit loath to take the mast off just to have a look.

Any suggestions gratefully received

Regards

Jim
 

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Dec 25, 2000
5,909
Hunter Passage 42 Shelter Bay, WA
Mast Step Leak

Your boat is of a different model, but if your boat is built similar to ours, the odds of water flowing through the mast step and down inside the compression post is unlikely. Our leak could be seen running down the outside of the compressions post and I repaired it as follows:

While Belle-Vie was on the hard for repairs awhile ago with the mast unstepped I addressed a number of minor maintenance issues including a small leak through the mast step into the salon.

The mast step is held in place with four SS flat head through bolts with lock nuts. This step has a drain hole on the head end bottom side so that rain water entering the mast head can drain out through this small hole at the bottom. The electrical wires run through a short piece (original was two inches long) of one inch plastic PVC pipe that is inserted in a hole in the coach top. You can see this piece of pipe if you remove the covering from the top of the compression post.

The pipe is supposed to be sealed, but over time this seal failed, so water coming from the mast head would leak around this pipe and into the salon. The PO tried to use Silicone II from inside the boat but that did not work.

After cleaning the cast aluminum step plate and coach roof surface I used 3M4200 sealant to rebed the plate. The new three inch piece of PVC was placed with a liberal amount of 3M4200 around where it entered the coach roof. The PVC pipe extends about two inches above the coach roof so that any rain water pooling at the base will run out through the weep hole in the step plate. Be sure to leave a drip loop in the wires that enter the coach roof.

Each season I use a pipe cleaner to clear out any debris in the step plate weep hole. This repair was done in 2002 and it still remains dry.
 
Last edited:
Dec 25, 2000
5,909
Hunter Passage 42 Shelter Bay, WA
Another Possibility

Our model is also a center cockpit. Another source for rain water entering the boat is through the two transom deck level lockers port and starboard. Our lockers have a drain trough around the lid sill with a drain system so that water will collect around this trough and out a through hull.

If these drain ports become clogged as they did in our case water will spill over the trough, down into the area beneath the aft cabin berth and into the bilge. It took awhile for me to find the source, but a quick blast with a city water nozzle cleared out the drain ports. At the beginning of each season, when I clean the boat, I use the hose nozzle to clear out that drain system. A heavy rain could easily overwhelm this drain system and could be another source of fresh water in the bilge.

When we first took possession of Belle-Vie and were cleaning her up stem to stern, I noticed that a small well by the rudder quadrant was full of fresh water. Hmmm, source? Pumped all the water out and it remained dry for a few seasons. Then it was full of fresh water again. It was not until I made the connection between the plugged drain port that I discovered the source. It has been dry ever since...six years now.
 
Last edited:
Jan 28, 2017
44
Hunter 34 Halifax
Hi

I have a 460 in the UK which has a leak I am trying (frustratingly) to trace.The boat is out of the water by the way.

I think it is coming in via the mast step and then travelling down inside the compression post exiting at the bottom. I found water there today (see photo) and about a gallon in the bilge - which I had dried out last week. We have had a lot of rain.

I believe the mast compression post is hollow and can see from underneath where it pokes through a hole in the deck presumably to sit under the mast deck plate. I believe the deck plate is solid apart from the bolt holes which are dry on the inside.

I can find no water in the area under the deck hence why I think it must be travelling under the deck plate and then down inside the post. My confusion is how so much water is coming in as I am struggling to find any significant gap at deck level and am a bit loath to take the mast off just to have a look.

Any suggestions gratefully received

Regards

Jim
Hey Jim, I have the same issue with my 460. did you ever resolve the issue? any insights.