Please name this Fiberglass structure used in place of "Stringers" for engine mounts

[cadmus]

Originally Posted by Squanderbucks

I’m not too excited about recommending keeping the original setup. The “pan” or tub portion seems pretty flimsy and the engine weight does not seem to be supported directly by any heavy structure. The engine mounts are not supported by anything solid.
I would ditch the molded tub and remove the paint along the sides of the real stringers just outboard where the pan fastens. Square up the surfaces with fiberglass Ind wood if needed. Then have either two long or 4 Shorter aluminum right angle mounts bolted in place. These are often made from 1/2” thick alum
Then put your engine mounts through bolted to the new aluminum brackets.

Much more solid and leaves you access to the new replacement tank in the future.

Examples of these types of mounts are shown for powerboat applications at Seaboard Marine ( submarine.com )

Thanks, I think what you are describing is what was on every boat I owned thus far; glassed timbers.

And I would Jerry rig angle iron to improve the lag screw, i think that is what you are suggesting.



The structure is not flimsy. It is 3/4" of fiberglass. (thicker in the pan but likely cored with ply) I am very impressed with it. My guess is it was installed to let water from the stuffing box make its way over the tank to the bilge. But in addition it looks to be very stout and distribute the mass of the engine over far more surface area.

[cadmus]

I am late for work but look forward to responding to the other nice comments left here as soon as I return. Thanks

[Grey Goat]

"The structure is not flimsy. It is 3/4" of fiberglass. (thicker in the pan but likely cored with ply) I am very impressed with it. My guess is it was installed to let water from the stuffing box make its way over the tank to the bilge. But in addition it looks to be very stout and distribute the mass of the engine over far more surface area."

Good to hear. But given how easy it is to make the stringers bear on the hull, I would still do that.

[cadmus]

I wanted to thank all those that weighed in on both the name and how they would proceed. Even with the multitude of alternative names I was unable to trace down the origins of the engine bed that is bridged over the fuel tank. It is likely original but was not used by NorSea yachts long because no one on the NorSea forums has seen such a thing including those with hull numbers near mine. I base this guess only on the fact that the tank welder's info placard listed the purchaser as the manufacturer and that the GRP layup to the hull extended will beyond (under) the factory cabinetry, there is no sign of other mounting systems found under the bridge bed stringer thinger dinger. As someone in this thread stated and as I stated, i bet it was to allow dripping of the sterntube to make it's way over the tank to the bilge. Also, as a center cockpit, the motor is moved forward relative to all other boats I worked on which had the motor further aft. The 14.5" width of the engine mounts is narrower than the width of the keel. So, i assume the builder gave this a try for that reason also. Maybe not. I surveyed many NorSeas with the old standard of GRP covered timber beds/stringers/rails.... Most were properly soggy and saturated inside the timber (it was a joke, relax).



It broke my heart, but i cut the thing out. OVERBUILT. REALLY THICK. Then spent my COVID-19 social distance summer slowly sawing and prying the tank out of the keel. I felt I should post photos for archival reasons in case someone searches with similar problem in the years to come.

Debating how to proceed. The laying of a GRP integral fuel tank is likely the BEST option. My hands are too big to lay that in the narrow area below the stern tube. It would extend my fuel capacity and motor range a great deal (estimated by the density and total weight of the foam I chipped out of there). Encapsulating another aluminum tank in a hypoxic galvonic nightmare of expoxyfoam is NOT what i WANT to do. It is what most the other owners have done, everyone has this issue with NorSea27s. Sadly, moving the tank elsewhere is not an option and deckspace it too limited to rely on the jerrycans nor do i like the liability of that windage in a storm. I considered swapping a water tank for a diesel tank. It just makes sense where it is. Another option for the fuel tank is have an open air tank and lets the bilge water slosh back and forth under it so I have 8 feet of grimy stinky bilge space that will never be scrubbed.

It is too cold to lay glass until mother's day 2021. I hope to have a plan and parts ordered by then.

[Cadence]

If I read it correctly, water or fuel you might consider putting a couple if webs in to minimize a fore and aft furling effect.

[cadmus]

Originally Posted by Cadence

If I read it correctly, water or fuel you might consider putting a couple if webs in to minimize a fore and aft furling effect.

Webs in the tank? or webs in the engine stringers?
I had to cut the engine pan/stringer/bridge out to remove the tank.

Please define what you mean by furling effect.
Many thanks,

Pete

[Cadence]

Originally Posted by cadmus

Webs in the tank? or webs in the engine stringers?
I had to cut the engine pan/stringer/bridge out to remove the tank.

Please define what you mean by furling effect.
Many thanks,

Pete

Webs in the tank. Furling effect is basically sloshing which would allow the weight of the water to move the length of the tank when not full. It might contribute to hobby horsing running freely fore and aft in the keel. Just a thought.

[mike d.]

Those would be baffles to stop sloshing ! Cadmus we have a fiberglass fuel tank in our boat ! The tank was made outside the boat completely as a sealed canister/container ! The access is through the inspection plate at the top, which also has the fuel fill. fuel to engine, and return line ! It is 41 yrs old ! I was the 1st to take the lid off about, 6 yrs ago ! Other than red stain from the fuel dye it was clean as a whistle ! It is gel coated inside which may have helped !

[cadmus]

Originally Posted by Cadence

Webs in the tank. Furling effect is basically sloshing which would allow the weight of the water to move the length of the tank when not full. It might contribute to hobby horsing running freely fore and aft in the keel. Just a thought.

Per code it needs only 1 baffle. If i do 2 I will add an extra inspection port.

[cadmus]

Originally Posted by mike d.

Cadmus we have a fiberglass fuel tank in our boat ! The tank was made outside the boat completely as a sealed canister/container ! The access is through the inspection plate at the top, which also has the fuel fill. fuel to engine, and return line ! It is 41 yrs old ! I was the 1st to take the lid off about, 6 yrs ago ! Other than red stain from the fuel dye it was clean as a whistle ! It is gel coated inside which may have helped !

Thanks Mike D. Yes, i do want to do a GRP tank out of vinylester. I have not found a easy way to make it outside the boat that does not waste a great deal of volume. Laying it in keel (integral) or outside it would require glassing in a tight thin shape as the aft of the keel is narrow. My gorilla hands might not fit. (male mold outside the boat would avoid this). Outside would allow me to not lay glass in a more comfortable position with gravity helping me. If i make it outside the boat I would reduce the dimensions significantly and then have to epoxy foam it like the other tank. Still waiting to hear if a HDPE or polypropylene tank can be "plastic welded" custom.



Is your tank in the keel?
What is the hatch area relative to the area of the tank?
I feel like giant aluminum hatches would make it feasible, allowing the internal tapping/seaming to be layed upside down.

[Cadence]

Originally Posted by cadmus

Per code it needs only 1 baffle. If i do 2 I will add an extra inspection port.

If you are making the keel a tank, Which sounds like a good idea. i have no idea who's code that would be?
Inspection ports are cheap. I think I would stick with water not fuel. As I said baffles were just a thought. Make sure you use an non leaching resin.
Best of luck.

[mike d.]

If you make a mock up panel to span the width of the keel, and transfer that to making it out side it would work ! Ours was made this way, and then set in resin spooge, and glass to hull at the top, and along the forward, and rear edges. To not loose alot of volume, could you not extend it over the bulkhead which was at the forward end of your old tank ? just a thought !