Foam in forward bilge

[garylinger]

A PO apparently sprayed or had sprayed a dense foam in the blilge beneath the access panel located under the steps (S2 9.2C). The bilge under the diesel is open and free of any of the foam. When the surveyor did his thing last summer he scratched his head and said he didn't know why it would be there. Has anyone ever encountered this? I am tempted to start removing it but if it was put there for a specific purpose I don't want to create a problem. It seems to prevent water from having a direct path into the bilge from the forward part of the boat (I discovered today that my fresh water fill hose became disconnected from the tank and some water leaked out and was lying just under the cabin sole). What are the various opinions?

 

[NotCook]

Foam Hull Liner

Hi Gary, Our boat has a full 3" foam insulation liner, with teak liner inside that. The benefit is to keep insulated from heat or cold outside. We might assume that is what the PO was after. The downside, as you are experiencing, is that if it gets saturated, it holds in moisture. We are fighting a similar problem right now ourselves. If I had a choice, I think I would do without it. I have no idea how you would remove it successfully. If you try, I think you are going to have a real mess. Hopefully someone else on here will have expertise as to how to remove the residue. My concern would be that any solvent that will dissolve the remaining foam insulation will also be harmful to the hull itself. I'm not an expert on either, so I'll defer to someone else on that. Good luck!

 

[Chuckbear]

If the foam is in front of or behind the engine compartment it may be an insulator to keep heat or noise from the engine out of the cabin. Just a guess since you did not say where it was in relation to the engine. Perhaps the PO did not like the heat when motoring. Chuck

 

[sailingdog]

Just remember not all POs do things with rational, good reasons behind their actions.

 

[sand sailor]

most foam is a poly resin reaction so acetone will dissolve it but good ventilation is a must.
cut out what you can and use acetone to clean up the rest , it may soften surface of the hull but when it dries it'll be fine if you get it all it wont be sticky , the acetone will melt the foam

 

[BobM]

Maybe they were trying to add postive flotation ;-)

Seriously though...probably noise reduction.

 

[garylinger]

The foam is in the FORWARD part of the bilge (forward of the bilge that is below the Yanmar) under the main cabin sole just below the steps. The surveyor mentioned "positive buoyancy" and then laughed, saying it would not work.... My thoughts were floor (sole) support??? Maybe sound proofing is possible but heat reduction makes no sense since the diesel is ABOVE the bilge. I'm afraid to remove it without knowing why it was put there.

 

[Ian4781]

Foam is not a material to use as a major repair item...unless injected under pressure as a core or in such things as rudder or centerboard construction.I would be more concerned about leaving it there and not finding a problem that the po tried to fix improperly.You could always reinstall foam if you find a good reason to have it there,however,most exposed foam will absorb water and will do little more than add weight.I would also be concerned depending on foam types about toxic fumes from unsealed foam in dry form and also in damp form where mold spores might take hold.