370 Gas Tank Replacement
benvenuttioki
Member Posts: 131 ✭✭
At the end of last year we discovered a leak in the starboard gas tank. I knew it would be bad, but I had no idea of the magnitude until the final quotes were in this past week. I'll have a lot to say about it, with pictures, in the future, but I need to make a quick decision on how to remedy a related issue found while the boat was surveyed by insurance.
The port vents to the engine compartment are wide open. Unlike the starboard, which have hoses run down toward bilge, the port vents allow any salt water to come directly in and fall onto... the port gas tank. Which now has corrosion. I bought the boat from Rinker and presumed the configuration was correct, but... The yard is worried about overly restricting ventilation by adding hoses. What is supposed to be there to keep water out?
The port vents to the engine compartment are wide open. Unlike the starboard, which have hoses run down toward bilge, the port vents allow any salt water to come directly in and fall onto... the port gas tank. Which now has corrosion. I bought the boat from Rinker and presumed the configuration was correct, but... The yard is worried about overly restricting ventilation by adding hoses. What is supposed to be there to keep water out?
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I literally put my nose on every fuel hose and connection I could get to in the engine compartment. Nothing. No smell at all back there. I called in someone from the boatyard. Nothing in the boat but "normal boat smells." BS. We had stopped using the boat by this point, but the weather was usually good, so we opened hatches and stayed aboard every weekend, still searching.
In late Sep I noticed that the mid-cabin area had a heavier odor. I removed the seat cushion on the starboard side, just aft of the electrical panel. It was coming from there, but there was no gas. No film. Nothing. I opened the mid-bilge. No odor. Odd. We washed out the area under the cushion and went home.
The next weekend when we arrived at night I could smell gas from the dock. I had left the cushion off and could see gas. Batteries were disconnected the next morning. Thankfully the bilge pump had not kicked on, but it was close. The boat was pulled, and offloaded. It was Oct and we were done.
My port side vents are wide open the same as yours. Starboard side has the hoses to the blowers.
Do they have to cut up the floor, or can they get the tanks out by removing the engines and generator?
Instead, find and fix the root cause of how water is entering through the vents. There's a cover to direct rainwater away from the vents, right? Did the factory forget to apply caulk to the seams? Or has the caulk failed? You should not be getting any water through the vents, except maybe a little splash when washing the boat.
Here is a photo of the top of the gas tank
When the blowers are on, air enters the bilge through the port side and through the transom locker vents and exits the starboard side.
After we got the boat out and gas out of tank and bilge, the effort to find someone to work on it began. Our "full service" boatyard wouldn't touch it, nor would they refer us to another yard in the area. Some of our slip neighbors recommended a nearby yard, so we had her put back in the water and towed over after winterization was complete. I contacted our insurance and they assigned a surveyor. Maybe I could get some coverage. By this time it was early Dec.
The surveyor couldn't assess anything until the tank was removed. The insurance couldn't determine coverage until the surveyor found a cause. The boatyard gave me an estimate of $20K, which the surveyor/insurance thought was a good price, so no other quoted were required. Oh, corrosion isn't covered by insurance, so if we started I was possibly (probably, I thought) on the hook for the whole thing. Merry Christmas.
Leading up to the quote I talked w/ the yard a lot about how to get the tank out and another back in. The fiberglass guy wanted to go the most direct route; through the hull. I was in favor of going the cabin bulkhead aft of the electric panel. Ultimately, we agreed to pull the fresh water tank, gen, and engine then cut fiberglass in the engine compartment to pull it out. When the yard opened back up after the holidays, the project manager I was working with had left and head of the yard had my boat. We decided to pull it out of the cabin.
The tank came out. It was bad. There were two holes in the bottom. There was salt all over the area where the tank came out. There were multiple lines on the side from where it was bathing in water. For a loooong time. Zoom in on the pictures.
The tank sat in a fiberglass pocket with rubber 1/8 in thick straps holding it in by compression. There was only that much clearance around the side. And there was no drainage. None. Any water that got in stayed until it evaporated hence the lines. Who the heII puts an untreated aluminum tank in a bathtub on a boat! I was pi$$ed. Still am. Mostly, I felt physically ill.
There was evidence of water dripping down from where the "arch" joined the deck. There was evidence of water running down the hull-deck joint under the rub-rail and dripping down. I also remembered that in '21 the blue plug on the starboard engine broke and salt water was spraying all over the water tank area when I happened to open the hatch while engines were running. I cleaned the area w/ fresh water, but at best that would have diluted what was already trapped, though I'm not sure if any water would have gotten that far forward.
Good luck and please keep us all posted.
The port tank is significantly harder to deal with. Over 2x. When I added the two together, panic set in. Is it worth putting the money into the boat? If it's not, how do I escape? Short sale? Parts? None the ideas made sense.
So, I'll bite the bullet and fix the starboard side and hope the port is not slowly rusting away.
- Replace tank w/ coated aluminum
- Create drainage in mounting location
- Add stand-offs to create air gap around tank
- Find and fix leaks in hull/deck and top for entire boat
- Clean port tank and replace fittings if required
- Add deflector on port vents (maybe)
I guess that's it. I gave them the authorization to proceed this week.So why am I posting this? I have no idea what I could have done to prevent the problem. How would you know there was no drainage? How would you know there was water accumulated? I never had much water in the mid-bilge to indicate a leak. Maybe, by airing my trials and sparking discussion, somebody else may avoid this in the future. I've made my peace w/ the situation and my decision. Now, I just want my boat back and be on the water this summer!!
Another possibility is that water is accumulating in the pan that is under your cockpit fridge/ice maker and draining down onto the tank.
I agree it is a terrible design to have the tanks sitting in their own bathtub. Your plan is exactly what I would do. Are you going to have the starboard tank repaired, or are you replacing it?
Started with removing risers on outside to clear edges. View is standing midship looking down into engine room towards stern.
Engines out. Standing on aft section of engine hatches. Under foot are three tanks- 135 gallons on each side and 60 in the middle.
Two of three tanks out. This view is from engine room looking aft. Last 135 gallon tank can be seen on left side of picture.
I'd pressure-test that port tank. The fittings look nasty.
I do plan to have them clear rust ant replace fittings if required on port.
About 10 years back a friend of mine had two Al tanks start leaking, in a houseboat. He replaced his with AL, we put strips of rubber under the tanks such as a thick 1/2 inch belt material. Not the thin stuff originally installed. To raise the tank enough. to create air flow and get them higher up off the floor. We used 3 inch strips of rubber as wide as the tank, one foot apart. Just an idea. So far that gremlin has not raised it's ugly head again for him. Feeling your pain.
From the looks of those pictures there is a lot of water coming in there. Can you get in there and have some one hose down the boat to see where it is coming from? Make it rain. Find it hard to believe it's coming from those vents. Maybe it is.
Thank you for the update.