Marine Trader Bilge cement ballast removal

Good morning,
I have undertaken the project of removing the old cement/stone ballast in my marine trader. The fibreglass cloth that covered the floor of the bilge area and cement was loose and allowed water, oil, fuel and general debris to seep down into the keel for years from the previous owner. I was concerned that the water in the keel in would freeze and split the keel. I did not want to install a keel drain plug without viewing and cleaning the area.
Yesterday I used a hammer drill and removed about 200lbs of the old cement/stone mixture. The keel and bilge smelled awful with its removal.
Has anyone else ever done this project? I am thinking of leaving the keel cement-free and using it as a sump area.
I will post photos.

Older Willards have concrete ballast. Some owners have removed and replaced ballast (with lead), though tends to be hundreds or thousands of pounds as these boats carry up to 7000 lbs of ballast on the W40 (my W36 has 5000 lbs) . Ballast tends to be concrete with steel punchings and difficult to remove. Unclear from your note whether 200 lbs is all of your ballast, or just a portion of it.

I am in the process of replacing close to 2000 lbs concrete ballast not because of deterioration but to accomodate a reconfigured stateroom and install a bow thruster. It took two workers over a week to ger the old out. Replacement will be lead ingots and lead shot held in place with resin. Pouring that much resin is tricky due go exothermic heat release. Not sure what protection from excess heat is used

Before removing ballast I would have to ask myself, why is that ballast there and how will it affect the boat handling if removed?

I thought that too, which is why I asked if the 200 lbs was all, or if it was part of the ballast (who knows, maybe a typo and really meant 2000 lbs ballast).

If it's only 200 lbs, that's roughly equivalent to 30-gallons of fuel. Shouldn't really effect anything. But I agree - why did they bother? Maybe extra concrete and needed a place to dump?

I can't find any references to the MT 38 Sundeck having any ballast at all. I'm wondering if it was lightened some how and the ballast was used to bring her back down on her lines. 200lbs wouldn't do much in a boat that big. 2000lbs may bring her down an inch to an inch and a half. Maybe they wanted to fill in the keel and not have a deep keel. If the weight isn't needed, I would fiberglass it in with a shallow sump for a bilge pump and install a sealed deck hatch for inspections in case of grounding.


I like how Mads (pronounced Moss) reworked his deep keel/bilge area in this video. He gives good reason for why he does it his way.

On a previous boat, a Trojan F32, the hollow keel had accumulated water over the years. When we bought the boat the hollow keel water had begun to stink and stink badly. I ground off the thin covering fiberglass to open up the keel. The boat was a 1978 model so the water had been in there forever. By opening it up I was able to scrub the keel clean and got rid of the stink. I mounted a Whale pump with a remote pickup down in the keel to pump out the water. We never had the stink after opening the keel up.

I also would be surprised if there was only 200 pounds of ballast in the keel. I would replace the cement with an equal amount of lead and encapsulate it with epoxy. Then maybe put a false bottom on top of the lead and glass it in so no water could get down to the lead. You definitely want to keep water out so it doesn’t start to stink.

Great video. Love the fiberglass ribs on that boat - looks hell for stout. The owner does nice work.

Concrete is not a great ballast material. Especially if bilges are allowed to be wet. There are additives that can be added to concrete that help a lot, and my ballast looks healthy. I have three tranches of ballast - front (800 kgs removed), aft (guess around 400 kgs) and center/engine room of around 1200-1500 kgs (guess). The only one I am touching is the forward one, and only so I can do some other work. Lead is about 5x more dense than concrete so can free up some space and get the weight lower, though since my boat is a full keel displacement hull, the bilge is pretty deep so may need a false bottom as in the video. Getting that much lead encased in resin without excessive heating will take several pours. For the other areas, have covered with a half inch of floor leveling compound to make it smooth and let it run down sides where there are some small spaces between the hull and ballast. I may glass over it and wrap into the stringers, but not sure. My boat has a pretty dry hull so I'm not too worried.

Hopefully OP will respond. Curious to know more about his situation. Seems odd, but sometimes yards do odd things. They are often decent at general construction but don't have a strong sense of the quirks of a boat.

SirJohn said:

Good morning,
I have undertaken the project of removing the old cement/stone ballast in my marine trader. The fibreglass cloth that covered the floor of the bilge area and cement was loose and allowed water, oil, fuel and general debris to seep down into the keel for years from the previous owner. I was concerned that the water in the keel in would freeze and split the keel. I did not want to install a keel drain plug without viewing and cleaning the area.
Yesterday I used a hammer drill and removed about 200lbs of the old cement/stone mixture. The keel and bilge smelled awful with its removal.
Has anyone else ever done this project? I am thinking of leaving the keel cement-free and using it as a sump area.
I will post photos.

Click to expand...

Hi,
We have a similar problem with our 34' MT, how did your "fix" work out with the keel?
Anxiously awaiting your reply!!!
SV Pendragon

MT 34' keel issues

Hi,
Wondering how the keel issue problem worked out on that 36' MT?
sp