Bought a 1998 Sea Ray Sundancer 270 wide beam with rot...

alldodge

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Hand saw is the safest, if you can get a lot of air moving like with fans that would be an option if the hand saw doesn't get it
 

drewm3i

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Update: was able to remove the fuel tank pretty easily after carefully planning my course of action. That panel did indeed remove quite easily which allowed for more clearance so I did not cut the bulkhead. Once i siphoned out the gas with a very good hand pump drum siphon, the tank was so light I could lift it myself. I am now ready to start gutting this boat and the rot goes all the way up to the cabin bulkhead on the one side and is nonexistent (I believe) on the other per the hammer test. The aft cabin bulkhead seems solid though. Here are some pictures:

Starboard main stringer is GONE:


Aft bulkhead is almost completely removed as well:


Forward cabin bulkhead seems solid:


Beneath the tank is gross, I think I am not going to reinstall a drain at the bottom of the aft bulkhead. Why would I want bilge water under my aft berth?


Starboard stringer raised view:


Top view:
 

tpenfield

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Nice update . . . aren't boats fun :rolleyes:

I would get a $30 moisture meter (from HD or Lowes) and drill slightly through the fiberglass coating on the stringers in a few places and . . .

1) see how wet the starboard stringer is as you go forward toward and to the cabin bulkhead . . .

2) same thing on the port stringer, even though it feels solid, you want to know how wet it is inside. (my feeling is that it is going to be wet since it was connected to the rear bulkhead.

Yes, that fuel bay is gross looking . . . :D
 

drewm3i

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Good idea Ted, though I will say that the aft bulkhead is solid on the port side if you look closely at the pictures.
 

tpenfield

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Good idea Ted, though I will say that the aft bulkhead is solid on the port side if you look closely at the pictures.

Yes, probably is solid . . . what you need to determine is if it is wet, because if it is wet then that will someday rot if you do not address it in your current repair work
 

Mikeopsycho

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Agree about your not wanting bilge water under the aft berth, I'd omit the drain hole too. Is this a hollow area with no access? If so, it could be foam filled to help keep moisture out.
How's the fuel tank look? Will you be re-using it? Sorry if you already mentioned this, I don't recall.
 

drewm3i

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Agree about your not wanting bilge water under the aft berth, I'd omit the drain hole too. Is this a hollow area with no access? If so, it could be foam filled to help keep moisture out.
How's the fuel tank look? Will you be re-using it? Sorry if you already mentioned this, I don't recall.

No worries and welcome to the thread! The tank is plastic so yes it is perfectly fine. The compartment behind that rotten stringer may be partially foam filled. I will find out for sure soon.

Ted, if the bulkhead is wet I will probably let it dry out and then treat it with an epoxy as I have no access to it from the cabin without getting too crazy, which I am very apprehensive about doing as the cabin floor is glass...I will keep gutting and updating this thread.
 

tpenfield

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Ted, if the bulkhead is wet I will probably let it dry out and then treat it with an epoxy as I have no access to it from the cabin without getting too crazy, which I am very apprehensive about doing as the cabin floor is glass...I will keep gutting and updating this thread.

Yes, addressing it does not necessarily mean replacing it. If you can get it to dry out, then maybe give it a drink of ethylene glycol cool-aid. :)
 

Roady68

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Some good progress there. As for moisture meter, I had done a lot of research. I don't think the ones at Home Depot work through fiberglass. They need to be directly on the wood as they have two pins and use conductance. The more expensive meters that marine surveyors use are capacitance and more accurate for boats. But they are $$$$. At least that is what the research I did taught me. I bought the same unit a local surveyor uses. You should see if there is a surveyor locally that may just meter a bunch of areas for you. Maybe buy him lunch or slip him a $20 (or $40?)
 

tpenfield

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Some good progress there. As for moisture meter, I had done a lot of research. I don't think the ones at Home Depot work through fiberglass. They need to be directly on the wood as they have two pins and use conductance. The more expensive meters that marine surveyors use are capacitance and more accurate for boats. But they are $$$$. At least that is what the research I did taught me. I bought the same unit a local surveyor uses. You should see if there is a surveyor locally that may just meter a bunch of areas for you. Maybe buy him lunch or slip him a $20 (or $40?)

Yes, the inexpensive moisture meters need to be in direct contact with the wood and cannot work through the fiberglass . . . but . . . if you are ripping apart your boat for a repair, what difference is a couple of test holes through the fiberglass and into the wood going to make? Once you get the results, you can always just seal them back up.

The meters that the surveyors use give an approximation of how wet the wood is by measuring how wet the fiberglass is, based on its conductivity, therefore the higher cost.
 

drewm3i

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Update: Progress has been slow as I have a lot going on and I'm taking my time for sure, but I am definitely making progress. The gut has begun and I have been drilling holes everywhere to look for rot. Bad news is that the lower portion of the transom is mush so I will need to replace that, but so far I have found that the rot is only in the central part of the structure. From what I can tell, the port central stringer is not compromised. Low core samples came back negative. The starboard stringer though is rotted extensively and I worry about the aft cabin bulkhead. The engine mount stringers were also very rotted, but the skins are in good shape. The outboard stringers are good per core samples. Here are some pictures:

Starboard stringer is toast. Not sure where the water intrusion came from, but I'm guessing it's all from bilge water:


Bulkhead removed, stringers gutted:




Transom taps solid, but bottom end is toast:


 

alldodge

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Something has been leaking for a good while, you should be able to find the location with enough digging. You can do a partial transom replacement, but full replacement is easier to keep everything flat.
 

tpenfield

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In terms of your question about the propagation of moisture and the ensuing rot throughout a boat's wood structure . . .

It only takes 1 or 2 voids in the glassing or even a section that was missed in the production cycle . . . then the boat will absorb water and the wood components, many of which are connected to each other prior to the glassing will pass the moisture along from one part of the boat to the next. 15+ years later and this is what you get.

I don't think that any wood structure boat is 100% dry after 15-20 years. Some are just wetter than others . . . :rolleyes:

Anyway, it looks like you are in the midst of it and still finding the extent of the moisture and rot. You may not have to do the full width of the transom, because rarely are the outer portions wet/rotted. You may want to do the middle section where the transom assemblies mount to its full extent to make sure you get and even mounting surface, etc.
 

drewm3i

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As a note, there is no way I am replacing the whole transom. First of all, it's pointless and a waste of time so why bother. Second, the affected area is very small. It is the area stemming out of the drain plug rot, in addition to the area near where the rotten center stringers attach to the transom. It barely even makes it to the keyholes. My plan of action is to cut the aft portion of those center stringers out for now, though I will glass them back in before filling the seacast fill of the stringers. This will also allow me to gut the stringers better as the tops are solid, while the bottom is mush. But a question I have is what is the best tool/method to cut out the bad parts of the transom without harming the hull?
 

Roady68

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... clip... But a question I have is what is the best tool/method to cut out the bad parts of the transom without harming the hull?

Drew, I picked up a small battery powered circular saw. The blades are 3.375" diameter. You can set the depth to cut through the layers you wish. Works pretty well. Only down side is that the battery on the back of the handle makes it a little tough to use in tight areas. Also, because the blade is round, you need to go past the end of the cut line a little more to ensure the deepest part of the blade cut through what you wanted. I also picked up an oscillatory saw. That also works well, but I find that it takes longer to do the same cutting the circular saw did.
 

tpenfield

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Depending on how much of the engine stringers you cut back to access the transom . . . will determine what tools you could use. Lots of folks use a circular saw set to a 'safe' depth and then use it to make a checker board pattern in the transom wood. then they go at it with a chisel and knock the 'squares' off and use sanding/grinding to get the remainder of the wood and down to the outer fiberglass.

since you are working such a small area with reduced access, maybe a smaller circular saw or similar tool to make the 'checkerboard' :noidea:
 

drewm3i

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I don't think I have a circular saw, but I can get one. I do have an oscillating tool though! I will look at it and think a bit before proceeding.
 

drewm3i

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Could I not just use an angle grinder to cut the fiberglass away from the transom?
 
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