I am trying to get the old gas tank out and after cutting away as much as I could from the bildge and deck I have found that the only way I will get it out is to cut out the bulkhead that exists between the main and auxiliary (aft) tank. Do I need to replace it, ie is it structural. If it is structural could I move towards the BOW by 8 inches? I would keed the upper part of the bulkhead that the two deck plates screw into. Any input is much appreciatd.
Is the inter tank bulkhead structural 1994 Grady White 228
- Thread starter GreenRoomSon
- Start date
Hookup1
GreatGrady Captain
- Joined
- Oct 16, 2007
- Messages
- 3,155
- Reaction score
- 895
- Points
- 113
- Age
- 70
- Location
- Cape May, NJ
- Model
- Islander
I did fuel tanks on a 268 Islander. Different boat but similar problems. The process is documented here. Bulkhead removed and replaced. Step had to be cut to lift tank out. 1' square cut on gunnel to get to fuel fill hoses.
Decided that this is the year to replace my 25 yo fuel tanks. No leaks. I plan to keep the boat. I'll document the process here.
Pulled the hatch. This hatch was rebuilt a few years ago with Coosa board. Looks good and feels solid. Hatch was set with 3M 4000 - kept everything sealed. Some difficulty cutting with blade to get it up. Not sure what it will go down with. Deck ports were caulked in from the underside as well. Kept the tanks dry.
I also put plastic over the fill, sending unit and pickup. This deflects any water away from the busy area of the tank.
...
Pulled the hatch. This hatch was rebuilt a few years ago with Coosa board. Looks good and feels solid. Hatch was set with 3M 4000 - kept everything sealed. Some difficulty cutting with blade to get it up. Not sure what it will go down with. Deck ports were caulked in from the underside as well. Kept the tanks dry.
I also put plastic over the fill, sending unit and pickup. This deflects any water away from the busy area of the tank.
...
Timcan
Well-Known Member
- Joined
- Apr 11, 2020
- Messages
- 100
- Reaction score
- 71
- Points
- 28
I did this on my 1999 seafarer 228. No need to cut the bulkhead just cut the top cap that’s on the bulkhead. You have to also grind the lip where the fuel tank hatch sits on to get the tank to slide out( my tank was larger then the opening). I’m assuming your boat is similar to mine. Feel free to pm me also post some photos.
Attachments
Hookup1
GreatGrady Captain
- Joined
- Oct 16, 2007
- Messages
- 3,155
- Reaction score
- 895
- Points
- 113
- Age
- 70
- Location
- Cape May, NJ
- Model
- Islander
Smith1
Member
- Joined
- Feb 22, 2025
- Messages
- 8
- Reaction score
- 0
- Points
- 1
- Age
- 24
- Model
- Sportsman
The bulkhead you’re referring to likely provides some structural support and rigidity to the deck and surrounding area. Before cutting it out completely, check if it ties into any stringers or supports that contribute to hull integrity. If you need to remove it, reinforcing the area with a new bulkhead (even if repositioned) would be a good idea. Moving it forward by 8 inches might work, but make sure it doesn’t interfere with weight distribution or weaken overall support. If unsure, consulting Grady White or a marine surveyor could help ensure safe modifications.
My marlin has a bulkhead between the tanks I had to cut in order to pull the tanks. I contacted Grady beforehand and they suggested I put blocking in and just screw the bulkhead back in. I ended up glassing it in. It was easy enough.
Yes, the bulkhead between tanks is structural. Yes, you could easily move it by 8" with no issues.
The purpose of the bulkhead is to prevent collapsing/bowing of the stringers towards each other. How you actually accomplish that can be done a couple ways and one is likely not "better" in the end... but I prefer glassing. Although if you have trouble getting the forward side of the bulkhead to glass it, then blocking is the way to go... with some added glass where you can.
Consider... glassing the new bulkhead ahead of time in the spots you won't be able to reach once it's in place (especially edges).
Do not use pressure treated plywood.
The purpose of the bulkhead is to prevent collapsing/bowing of the stringers towards each other. How you actually accomplish that can be done a couple ways and one is likely not "better" in the end... but I prefer glassing. Although if you have trouble getting the forward side of the bulkhead to glass it, then blocking is the way to go... with some added glass where you can.
Consider... glassing the new bulkhead ahead of time in the spots you won't be able to reach once it's in place (especially edges).
Do not use pressure treated plywood.