I recently purchased a Sparkman & Stephens 30. I'm in the process of restoring her. The following is an account of today's investigation into the keel, and some questions I need assistance answering. You can also read the full account on my blog of the project here: Searching for Even Keel ? Sparkman & Stephens 30' Restoration
Today I figured I'd try to investigate a bit more what was happening with the keel. It seemed to have a lot of blisters and I was very worried that the keel bolts were sitting in water and corroding. I punctured some of the blisters last night and today the keel was streaked with fluid leaking out:
http://www.ss30.konnichiwa-japan.co...2016/02/image-10-e1454845990750-1024x768.jpeg
So I started by carefully grinding out the worst of the blisters, and trying to identify and check the keel seam. Pretty soon though, I realized that a lot of the fiberglass laminate over the lead keel was totally saturated with water, and peeling off. I stuck a scraper in and it went right under the laminate, then with a bit more pressure, in all the way. A solution of vinegar-smelling styrene leaked out.
http://www.ss30.konnichiwa-japan.co...2016/02/image-11-e1454846017994-768x1024.jpeg
http://www.ss30.konnichiwa-japan.co...2016/02/image-13-e1454846107436-1024x768.jpeg
The entire keel was saturated with water, which was decomposing the fiberglass in a chemical stew. I proceeded lifting up edges with the scraper, and pretty soon two foot long strips of old fiberglass were peeling right off. The port side of the keel came right off like that. It was totally saturated with water. The starboard side was a bit tougher, there was a bit less water and the bond to the lead keel was stronger. I'm not sure why, perhaps there was less water intrusion on this side, or perhaps the sun was shining on the starboard side when it was glassed and the resin set harder. Or perhaps it had something to do with this perplexing hole in the lead I found on the port side:
http://www.ss30.konnichiwa-japan.com/wp-content/uploads/2016/02/image-20-1024x768.jpeg
You can just see it in the above picture, about 8 inches down from the keel seam, maybe 18 inches back from the leading edge, about 8 inches forward of dead centre. Kind of in the middle of the patch of sunshine. Here's a closeup of it:
http://www.ss30.konnichiwa-japan.com/wp-content/uploads/2016/02/image-19-1024x768.jpeg
This is very weird. It looks like a piece of wire, the size of a coat hanger, set into a hole in the lead. It's the right height to line up with the bottom of the J-bolts, but it's obviously not a bolt itself. What is it for? Did water get in through there and corrode the keel bolt? I don't know. I figured the keel was the victim of a hard grounding, and had been extensively repaired. Sure enough I found a baseball sized dent on the leading edge at the bottom.
I became very worried about the status of the keel bolts. If they suffered a hard knock, then the keel wasn't sealing properly and they got corroded the keel could theoretically fall of in rough weather! The standard method of checking stainless steel J-bolts in a lead keel is to remove the epoxy cap off of one in the bilge, remove the nut, and inspect for any signs of corrosion. I was surprised to find that the keel bolts weren't encased in epoxy, but in very old, crumbling silicon sealer of some sort. I thought this was a bad sign, and prepared myself to find a corroded, crumbling mess underneath. Instead I found this:
http://www.ss30.konnichiwa-japan.co...2016/02/image-14-e1454846139859-768x1024.jpeg
That nut looks brand new. When I got all the silicon off it was perfectly dry inside, despite water having sat in the bilge for who knows how long. I couldn't believe it, so I figured I'd better take the nut off and really inspect the bolt. I borrowed a heavy duty 35 mm socket and breaker bar from the Marina, expecting a real fight to get it off. But to my surprise it came loose with about 30 pounds of pressure then spun free like a top. The washer/backing plate underneath was also clean:
http://www.ss30.konnichiwa-japan.co...2016/02/image-16-e1454846181865-768x1024.jpeg
And the bolt itself clean with no signs of corrosion:
http://www.ss30.konnichiwa-japan.co...2016/02/image-17-e1454846212402-768x1024.jpeg
This was really mystifying! These nuts & bolts are 40 years old. They should show some signs of age. Have they been replaced? But they couldn't have. The only way to replace bolts in a lead keel is to sister new ones alongside the old. This keel only has the six original bolts in their original position. I was really perplexed, so proceeded to remove the silicon caps from the other nuts and check them. All clean, shiny and new looking. There is no evidence of water leaking into the keel bolts from the bilge.
I was still worried about the possibility of water getting into the keel bolts down below though, so I thought I'd better inspect the keel to hull seal. Scraping of the fiberglass skin from the keel had revealed most of the keel seam, but there was still some epoxy and filler covering some parts. I ground this down enough to get a good look. The seam was clean, even along it's full length, and showed no signs of water getting in. There was a thin white bead of silicon sealant, still white, not yellowed, still rubbery, not powdery. This made no sense. Why was the keel so overbuilt with layers and layers of fibreglass if there was no leaking? I decided to grind down the thick fibreglass at the aft base of the keel stub to check for damage there. A hard knock to the leading edge could cause cracking of the hull and water leaking here. What I found was even more perplexing. This keel as a second keel seam about 10 inches above the seam where the lead joins the fibreglass! Why are there two seams? I've never heard of this before.
I thought it might be a crack rather than a seam, evidence of damage from grounding, but it's perfectly level on both sides, fair & even, and contains a thin bead of silicon. Why would there be a second seam? I've heard that some of these hulls used a shallow draft keel. Is this seam for an extension to the keel stub that would be removed for the shallow draft keel? The following two pics show the aft end of the keel, first port then starboard. Note the two seams running parallel to each other:
http://www.ss30.konnichiwa-japan.com/wp-content/uploads/2016/02/Port-seams.jpg
http://www.ss30.konnichiwa-japan.com/wp-content/uploads/2016/02/starboard-seams.jpg
So today's inspection of the keel resulted in more questions than answers:
I'm really stumped with all this. Does anyone have any answers as to what might be going on with this keel?
Today I figured I'd try to investigate a bit more what was happening with the keel. It seemed to have a lot of blisters and I was very worried that the keel bolts were sitting in water and corroding. I punctured some of the blisters last night and today the keel was streaked with fluid leaking out:
http://www.ss30.konnichiwa-japan.co...2016/02/image-10-e1454845990750-1024x768.jpeg
So I started by carefully grinding out the worst of the blisters, and trying to identify and check the keel seam. Pretty soon though, I realized that a lot of the fiberglass laminate over the lead keel was totally saturated with water, and peeling off. I stuck a scraper in and it went right under the laminate, then with a bit more pressure, in all the way. A solution of vinegar-smelling styrene leaked out.
http://www.ss30.konnichiwa-japan.co...2016/02/image-11-e1454846017994-768x1024.jpeg
http://www.ss30.konnichiwa-japan.co...2016/02/image-13-e1454846107436-1024x768.jpeg
The entire keel was saturated with water, which was decomposing the fiberglass in a chemical stew. I proceeded lifting up edges with the scraper, and pretty soon two foot long strips of old fiberglass were peeling right off. The port side of the keel came right off like that. It was totally saturated with water. The starboard side was a bit tougher, there was a bit less water and the bond to the lead keel was stronger. I'm not sure why, perhaps there was less water intrusion on this side, or perhaps the sun was shining on the starboard side when it was glassed and the resin set harder. Or perhaps it had something to do with this perplexing hole in the lead I found on the port side:
http://www.ss30.konnichiwa-japan.com/wp-content/uploads/2016/02/image-20-1024x768.jpeg
You can just see it in the above picture, about 8 inches down from the keel seam, maybe 18 inches back from the leading edge, about 8 inches forward of dead centre. Kind of in the middle of the patch of sunshine. Here's a closeup of it:
http://www.ss30.konnichiwa-japan.com/wp-content/uploads/2016/02/image-19-1024x768.jpeg
This is very weird. It looks like a piece of wire, the size of a coat hanger, set into a hole in the lead. It's the right height to line up with the bottom of the J-bolts, but it's obviously not a bolt itself. What is it for? Did water get in through there and corrode the keel bolt? I don't know. I figured the keel was the victim of a hard grounding, and had been extensively repaired. Sure enough I found a baseball sized dent on the leading edge at the bottom.
I became very worried about the status of the keel bolts. If they suffered a hard knock, then the keel wasn't sealing properly and they got corroded the keel could theoretically fall of in rough weather! The standard method of checking stainless steel J-bolts in a lead keel is to remove the epoxy cap off of one in the bilge, remove the nut, and inspect for any signs of corrosion. I was surprised to find that the keel bolts weren't encased in epoxy, but in very old, crumbling silicon sealer of some sort. I thought this was a bad sign, and prepared myself to find a corroded, crumbling mess underneath. Instead I found this:
http://www.ss30.konnichiwa-japan.co...2016/02/image-14-e1454846139859-768x1024.jpeg
That nut looks brand new. When I got all the silicon off it was perfectly dry inside, despite water having sat in the bilge for who knows how long. I couldn't believe it, so I figured I'd better take the nut off and really inspect the bolt. I borrowed a heavy duty 35 mm socket and breaker bar from the Marina, expecting a real fight to get it off. But to my surprise it came loose with about 30 pounds of pressure then spun free like a top. The washer/backing plate underneath was also clean:
http://www.ss30.konnichiwa-japan.co...2016/02/image-16-e1454846181865-768x1024.jpeg
And the bolt itself clean with no signs of corrosion:
http://www.ss30.konnichiwa-japan.co...2016/02/image-17-e1454846212402-768x1024.jpeg
This was really mystifying! These nuts & bolts are 40 years old. They should show some signs of age. Have they been replaced? But they couldn't have. The only way to replace bolts in a lead keel is to sister new ones alongside the old. This keel only has the six original bolts in their original position. I was really perplexed, so proceeded to remove the silicon caps from the other nuts and check them. All clean, shiny and new looking. There is no evidence of water leaking into the keel bolts from the bilge.
I was still worried about the possibility of water getting into the keel bolts down below though, so I thought I'd better inspect the keel to hull seal. Scraping of the fiberglass skin from the keel had revealed most of the keel seam, but there was still some epoxy and filler covering some parts. I ground this down enough to get a good look. The seam was clean, even along it's full length, and showed no signs of water getting in. There was a thin white bead of silicon sealant, still white, not yellowed, still rubbery, not powdery. This made no sense. Why was the keel so overbuilt with layers and layers of fibreglass if there was no leaking? I decided to grind down the thick fibreglass at the aft base of the keel stub to check for damage there. A hard knock to the leading edge could cause cracking of the hull and water leaking here. What I found was even more perplexing. This keel as a second keel seam about 10 inches above the seam where the lead joins the fibreglass! Why are there two seams? I've never heard of this before.
I thought it might be a crack rather than a seam, evidence of damage from grounding, but it's perfectly level on both sides, fair & even, and contains a thin bead of silicon. Why would there be a second seam? I've heard that some of these hulls used a shallow draft keel. Is this seam for an extension to the keel stub that would be removed for the shallow draft keel? The following two pics show the aft end of the keel, first port then starboard. Note the two seams running parallel to each other:
http://www.ss30.konnichiwa-japan.com/wp-content/uploads/2016/02/Port-seams.jpg
http://www.ss30.konnichiwa-japan.com/wp-content/uploads/2016/02/starboard-seams.jpg
So today's inspection of the keel resulted in more questions than answers:
- Why are there two keel seams?
- Why is the keel so overbuilt with layers of fibreglass?
- Why were the keel bolts in such good shape at the top?
- Why are both keel seams so apparently even, with good seals and no water ingress?
- Is it possible that the keel was dropped, re-set, sealed and heavily glassed over after hitting the rock that dented the leading edge? Would that explain the clean, new-looking keel bolts and nuts with silicon rather than epoxy caps, new-looking sealant in the seams, and level seating of both seams?
- Why was the lead part of the keel glassed over at all? To fair it up? To help keep out water? To help prevent oxidization? Is this necessary/recommended?
- What is the mystery hole in the port side lead?
I'm really stumped with all this. Does anyone have any answers as to what might be going on with this keel?