Keel Joint- Weird Issue

[bigd14]

I have an unusual situation a the keel joint. At least its unusual to me. The boat has been on the hard for a month. I just noticed what appears to be a sap like substance coming out of the keel joint at the exact same location on both sides of the boat. There was some minor bubbling/delamination at one of these areas at the haul out, so I suspect some sea water was getting into this area.

This substance just showed up in the last week. Its sticky like sap, dark brown, and smells strongly of epoxy (like when a pot of it goes off too hot). The "soft" spot in the keel/hull joint at this point is only about an inch long on the port side and there is not really a soft spot or bubble on the starboard side, but it is weeping this sticky substance too. The remainder of the keel joint is perfect.

Port side

Starboard Side

Keel joint

Any insight into what this is, and why? And why would it start coming out now, a month after the boat was dropped on the hard? I have not investigated the inside of the bilge yet, but survey found all keel bolts and nuts looked good. There was water in the bilge, which did not appear to be salt water (surveyor tested its resistance). I am going to grind into this area eventually, but figured I would try to arm myself with information first.

I'm really hoping not to have to drop the keel.

Thanks!

 

[KWay]

Ooze

So for me the first question to me would be is the bilge area clean, so I would check and make sure no oil or sludge is pooling around any of the bolts near where the stuff is leaking out of the seam. If it is the bilge then you can try to re-seal just the leak at the bolt or have the keel seam re-bedded. leaving it may cause long term issues with the integrity of the bolts.
If the Bilge is clean then the question is what was used to bed the keel in the first place? If the boat is pulled on a regular bases I would grind out the seam area and fair with some West System and check it again the next time she is pulled. I'm not seeing any real rust stains on the photos so it doesn't look like much or any water has been getting in.
Kent

 

[u079721]

I would agree with opening up those two areas and flushing them out with water (maybe using a syringe?) to remove any uncured resin, since that's probably what you're seeing. Fill the void with thickened epoxy, and maybe even put some cloth over the openings too. Then let us know how it looks next year.

 

[Christian Williams]

Clean, caulk, forget....

 

[bigd14]

I'll report back when I get a chance to dig into it. Seems weird that there would be a pool of uncured epoxy in there. The bilge does have quite a bit of spilled oil and diesel leakage from the PO and a leaky fuel tank, but this does not smell like fuel, just epoxy. And more like epoxy than polystyrene. Anyway, thanks for the responses.

 

[bigd14]

Finally got around to the keel joint. The port side had been weeping this sticky substance more as the weather heated up, as can be seen in the photo. This material smells very strongly of polystyrene. The fiberglass fairing shucked off easily with a knife. The entire keel joint was bedded in white sealant. In the middle where these leaks were, the sealant was sticky and the consistency of peanut butter over the length of about 4-6 inches. Otherwise it seems pretty sound. My next step before deciding to drop the keel (or just seal it up as is), is to undo the keel bolt nuts and see what there is to see in there. Two of the bolts have some mild rust stains (I think the same ones where the weeping keel joint is).

 

[Loren Beach]

Note: everyone should be aware of potential mistakes in terminology. There is NO epoxy resin in that joint from the time of build. It was all poly resin. Different chemistry.
The original seepage might well be a little bit of uncured resin. When this happens, it remains soft for a very long time, away from air.
Christian probably has the best take on it. i.e. clean out completely and "calk" with new resin. I would choose thickened epoxy.

To save curing time, a yard might choose poly resin filler, but just be sure that they do not use any cheap clay-based filler.
SCBW used to use West Systems for their work - I hope that the new owners are continuing to use high quality materials like that.

Let us know how this goes.

Regards,
Loren

 

[bigd14]

Good point, Loren. I wasn't trying to imply the keel was originally bedded in epoxy. Its just when l I initially noticed the sticky material it smelled like epoxy resin, so I thought the keel may have been rebedded with epoxy that was not mixed or cured properly. Once I opened it up yesterday it smelled very strongly of polyester or polystyrene. So I don't think it was ever bedded or rebedded in epoxy. At a minimum someone in the past put a white sealant like 4200 in the seam (some of which has softened or decayed), then faired over it with thickened epoxy and likely a very light layer of glass. Unfortunately they ran the fiberglass over the gelcoat on the keel stub and bottom paint on the keel, so the adhesion was poor and it pried up easily. I'm sure the poor adhesion allowed water to reach and ultimately penetrate a bit of the seam leading to the situation today. After sleeping on it I am leaning towards simply tightening the keel bolts, filling the seam with 4200 or 5200 then glassing over with epoxy and cloth, properly adhered to raw glass and keel metal of course. I know there is some debate about filling the seam itself with sealant or thickened epoxy, so I would love to hear recommendations. For thickened epoxy (whether in the seam or the fairing compound right over the joint) I will use West Systems epoxy with Cabosil and chopped fiberglass. I've found the fiberglass really helps keep the material from cracking. It's much more difficult to sand, but worth it for the strength.

 

[Rick R.]

I've seen the sticky stuff ooze from an area where the line organizer is on the cabin top. Opened it up and was please to find it was just uncured resin. Repaired and back to normal.

 

[bigd14]

Update on this. I ground all the glass away from the keel joint. Under the glass is a white sealant. This sealant is sound along most of the keel joint. It does not feel as tenacious as 5200. But under the "leaky" areas where the clear goo was oozing out, the sealant is soft and very sticky like uncured caulk, and very smelly like polyester. A thin spatula can be inserted deep into the keel joint and some of the material can be removed. The area on both sides of the keel are affected. The area where the sealant is failing is about 6 inches long and is in between two sets of keel bolts.

There was a diesel leak in the bilge so I am wondering if this is an indication that the diesel got into the keel joint and degraded the sealant in this area. So this has me wondering if I should drop the keel to try to get a better surface for sealant to adhere to. I'm kind of at a loss for now of what to do.

Does anyone know if diesel will affect any of the common sealants in use today?

Thanks,

Doug

 

[tenders]

Assuming the bilge is clean now I would not drop the keel over this. Reseal with 3M 4200, glass over with epoxy, and monitor. There are lots of keel-to-hull joints that are less-than-perfect.

 

[bigd14]

When retorquing keel bolts should I use a thread compound?

Thanks