Gulfstar sailboats

We have a 1981 SM 39 hull 54 that started leaking around the rudder post late last year.

When we hauled out last month, we repacked the rudder post packing gland.

No small feat considering there is a genset mounted aft of the Perkins. The first problem was that GS used steel setscrews to attach the rudder post collar to the rudder shaft (1.75" stainless solid). We had to drill those out and rather than drop the rudder we attached a new bolt-on collar on top of the original collar. After we loosened the collar, it was easy to pull the packing plate up (four bolts) and insert new packing.

When we dropped back in, no leaks at first but when we started underway we again got a minor leak.

On further inspection, it appears the bottom plate is loose as it turns slightly when we first turn the rudder and you can see water seeping from under the bottom plate.

...

We have had a leak problem in the same area on our GS50 which I have talked about before. May be totally unrelated, however after much effort in diagnosing the problem, I found it was water seeping in between the bronze rudder tube and the surrounding glass above the rudder, and working back in through the glass and coming out just below the metal plate you are describing. I tore the area apart last season and rebuilt the glass/epoxy bond and much of the deteriorated area. I have heard of similar problems with sailmasters. If the leak is not coming from the plate joint, it could be the same problem I have had. Won't relaunch again until this fall, but I'm hoping I have my leak taken care. Did have to drop the rudder for the second time to do the work.

Thanks - were you able to use the existing bronze rudder tube or did you have to replace that? Does that tube extend all the way down through the hull?

I never removed the bronze tube. Appears the problem develops because of a failure in bonding between the bronze tube and surrounding layup over the years, due to a combination of dissimilar materials, stress, and original layup. The tube goes all the way up through the boat.

After dropping the rudder, I ground back the area surrounding the lower end of the bronze tube at least 1 inch up. (this is important) The trick in doing this repair is to insure a good bond/seal to the bronze with the new glass and epoxy. I had some dialogue with the people at West Systems. Need to be sure to really rough up the exposed part of the bronze, then apply an epoxy/filler mix, then rough sand it while still tacky. (can be messy) This should help with the adhesion of epoxy to bronze. From then on, I kept building it up with glass and epoxy. It actually took several days to build the 1 inch area back up as I was doing it with thin pieces of glass. I think the many thin layers also help to insure a good seal.

I also ground out the area forward of the rudder which is where the water was working its way into the boat and coming out below the plate you described. The deterioration in the glass was apparent upon doing this. I ground almost totally through and slowly rebuilt the entire area. As I indicated, the boat has not yet been back in the water so I can't say if it's fixed, however I believe that area is more solid than it ever was and I think it's repaired as well as it possibly could be. I just don't trust any repair until I know it works.

Before proceeding on this course, I would suggest you look carefully at the suspect leak area. See if it is coming out from directly under the plate or possibly a hairline crack in the glass area below there, which was where mine was. The problem is the leak could be originating at the rudder tube but can come out wherever it works its way through the glass which can be different on different boats. If you determine that your problem is similar to the one I had and proceed with this repair, I suggest you take photos and/or video before and along the way to keep track of where you need to rebuild the glass to. ...

Watch out once [deck under mizzen] cracks, as water will start to seep in and you will have a mess! I first repaired my mizzen bed with a 4 X 6 piece of teak embedded in solid resin. Result: the roof in the inside started to give and rested on top of the partitions in the aft cabin. After some reflection, I decided that this was my own fault by creating a solid base with the bottom of the sandwich core. When the balsa is under, what stretches is the top under the base.

So be careful! Speaks loads of the strength of that top portion of the hull. My final fix was to locate the base of the mast, which came up in the midline aft corner of the shower stall aft, and went through it, as it came right on top of the propeller shaft, created a base on the tunnel, and placed a compression post in aluminum (3 inches) to the base of the mizzen, held in place by aluminum bases with rings and set screws. Works like a dream; roof in aft cabin is now back in shape, without resting in the cabin partitions. Cost of aluminum post and bases did not exceed $300. Planning and executing took about 5 hours.

The mizzen on my 43' is deck stepped. The deck under the step was cored. In 25 years a bit of water had seeped into the coring and the deck dented about 1/8" under the forward portion of the step. After unstepping the mast and removing the step I drilled four 3/8" holes 3/4" deep in a rectangular pattern 4"x5" and with a 3/4" blade cut out the top glass and balsa coring. Very little of the coring was rotten but the 4x5x 3/4" hole was dug and I filled it with epoxy. Solid.

The mast is directly above the juncture of the aft head bulkheads. On either side of the fore/aft bulkhead are pieces of teak approximatel 1"x5" that run from deck to sole and are through bolted together through the bulkhead comprising the compression post. Beneath the sole is a heavy piece of teak between the sole and the hull stringer that takes the support all the way down to the bottom of the hull. That piece I'll widen a bit to spread the pressure.

In 25 years of having a 30' mast sitting on it the balsa cored deck had compressed only 1/8" in the forward part of the step where the deck slopes up. It had sustained very little water damage even though there were no drain holes in the bottom of the mast. Now that I have fixed what really didn't need fixing I hope it doesn't break.

I have a 44 MKII ... I had the same problem with the deck under my mizzen sinking as some of the others but mine was due to the actual aft cabin sole being deformed by the weight of the mizzen from above. The mizzen is stepped on the topsides, which bears down through the shower wall to the aft stateroom floor. Since the shaft is directly under the mizzen there is no actual support to the hull itself, or wasn't until I added some new structural supports for the mizzen. Turns out the MKII had some fairly poor deck construction techniques used for the inside decks.

We bought our GS 39 new in '81 (hull #23) and kept it in Florida for two years, Lake Lanier outside Atlanta for four years and in Puget Sound since '87. When we pulled it out of the lake in '87 we had extensive blistering - many dozens up to the size of a quarter. The Seattle yard did a sandblast job (before the "peeler") which disclosed a poor bond between the outer and next layers of glass on the starboard side (only). Core sampling all around showed good lay-up otherwise. The fix was to grind off the starboard outer layer from waterline to keel, bow to stern, and re-glass. After a total of four months out of the water, the moisture meter showed everything to be nice and dry. Interprotect epoxy fairing and sealer followed. About $14K in '87 dollars - probably twice that today. No blisters since. We haul and paint the bottom every other year in this cool water.

The only clue (after the fact) that we had to the poor lay-up was some gelcoat fracturing (web-like) in the forward starboard area, apparently because of the poor bond during lay-up. Surveyor said it was "over rosinated."

I chalk it up to "luck of the draw" as opposed to anything I've heard over the last twenty years about general Gulfstar quality.

Re: Blisters

...

As a previous Catalina and Hunter owner, I can tell you that Gulfstar is a big step up in quality. Whatever you buy, look at the deck condition, quality and strength of the rig, quality of interior joinery, layout, in short the stuff you would not likely change if you bought it.

In the early 70's I worked for Gulfstar in St. Petersburg. Be assured it was a first-class state-of-the-art production facility. I know of no shortcuts that were ever taken that affected quality. Keep in mind we know a lot more now than we did then. BTW I trimmed the salon of the 50'er, you'll find my name on the forward bulkhead behind the starboard hanging locker.

We have a Gulfstar 37 and love it! It's about my 9th boat and the best yet. We live aboard here in Southern California and also plan to cruise down south next year.

One thing we noticed about the Gulfstars is that a lot of them had blister problems. Ours, a 1977 GS37, has had the bottom peeled and epoxied.

I've owned my '76 Gulfstar 41 Ketch since 1983; have sailed it offshore quite a bit, and work in the boating industry. I would agree they are well made, but prone to blisters in some boats, not in others. I don't know if this varied by specific crew, or what. Mine has quite a problem, which I keep ahead of by barrier coating etc. There are two problems which need to be looked at periodically. The seal between the bilge and the ballast fails, allowing water to surround the ballast, making tendency to blister much worse. I've had to redo mine twice. Getting it to fully drain so you can reseal requires you drill a hole in the bottom of the keel; you can't close the hole until all the water is out. And working under the engine is about as much fun as cleaning out horse stalls.

The rudder seal between the shaft stock and the rudder blade seems to open between each haul out. Twice on my boat and once on someone else's, I have cut open the rudder to inspect the shaft and webbing. They have been perfectly OK each time. If anyone knows a method of making a durable seal, I would sure like to know it, even though it seems more of an annoyance than a real problem.

The blistering of hulls of GS 41's is interesting to me; my 1975 41 (hull #160) has had no blisters in spite of long durations between haulouts. I did have her in the Great Lakes from 1993-2001 where she was hauled every winter. I have heard one theory that blistering might be caused by overzealous sanding, and I like that hypothesis because mine has been lightly sanded only once since 1978 (I painted her only every third year between 1979 and 1991) and have used ablative paint (Micron CSC) since it became available.

Alan: Even MIT who has researched the issue extensively cannot say for sure why some apparently identical hulls blister and others don't. Gulfstar is one boat that has some hulls which blister badly and others don't for no apparent reason. Heavy sanding could contribute, but since some hulls blister almost immediately, and others don't for 25 years, it is not thought this is the reason. There is some indication it has to do with the precision of the mix, and humidity at time of layup. Boats with a "hand layup" rarely have any structural problem, because each layer tends to be a barrier to further intrusion. The blister will be under the gelcoat, or go thru the first layer of mat, or perhaps the second, Once in a great while further.

... Anti-fouling paints, whether ablative or otherwise, appear to have no effect, according to tests. ... think mine is hull 162.

> Our 50 has the reported blister problem.
> We've barrier-coated and everything
> appeared fine for two seasons (we haul
> every year). The third year 82
> blisters appeared. I tend to think the
> problem has to do with water around the
> ballast making the hull wet throughout.
> How complicated is the procedure to rectify this?

The first time I did it was trial and error, which I have refined somewhat. My method is purely self-taught. Obviously the boat has to be hauled. Drill two 1/2" holes, one just below the seal (you may hit the ballast, stop when you do); the other at the lowest point of the keel. Let drain, while determining the character of the water running out. The big issue is whether or not you get petroleum waste with the water. Naturally, this will be towards the last of the water running out. Let it get down to a slow drip.

If there is oil or fuel residue, I flush from under the engine in the bilge with paint thinner. It is low cost, not very explosive and cuts the oil fairly quickly. It usually takes a couple of gallons, applied about 2 quarts at a time. Look at what is running out, and how fast the thinner poured in the bilge starts coming out the bottom. With the initial applications of thinner, I use whatever scrubbing instrument is available to loosen the crud and oil if any, from the bilge. You need to keep repeating this until the bilge is clean, and clean thinner is running out the lower hole. When the thinner looks clean, you then need to do soap and water wash of the bilge; I use Fantastic, but I'm sure there are others. Don't forget to rinse, using hot water if available. Let drip until it stops, usually a few days. If the sun is shining on the keel, or you can apply radiant heat to it, it will hasten the process a lot. Some people advocate pouring in alcohol which might work, but I haven't done it.

While it is dripping, you can redo the seal, and upper hole. I've been unfortunate enough to always have to work under the engine; It would be faster and a better job if the engine were out of the way. Bilge must be clean and dry. Ambient temperature between 60 and 80 is best. Use epoxy, not poly resin. Wipe all surfaces with an MEK-based cleaner (Intlx 202, etc) with lots of ventilation; acetone would work, but is way too explosive. Be very careful whichever, because the fumes are moderately toxic, a 3M mask with the right filters would help, but only a strong fresh airflow or supplied air is really safe. Cut pieces of fiberglass cloth to make convenient pieces to lay up. I use 2" tape for all seams, clipping darts where necessary to get it to lay in a corner. I also now use a biaxial loose-weave cloth which follows compound curves better. 6 oz is easier to use than 9 oz or 12 oz.

To do it right, wipe with one MEK wet cloth, followed with dry, and repeat until the drying cloth is completely clean. Mix up epoxy with slow catalyst (it runs into voids better) and paint a coat over all surfaces. As soon as it has kicked enough not to be easily moved, mix up a leveling batch of epoxy, hardner and collodial silica to be as thick as peanut butter, and spread over all surfaces, and radius every corner. Don't wait for it to harden. Lay Dry tape on all seems and corners, gently pressing it into the thickened epoxy, coat with mixed unthickened epoxy. Place pre-cut pieces of cloth over entire surface, coming up the sides at least 2"; coat with epoxy. lay on a second layer of tape as before; coat with epoxy, and a second layer of cloth, and coat. You can build up as many layers as you desire, but about 3 at a time is the practical limit, after which you need to wait until the epoxy has kicked. It is best not to let it fully harden before putting on more layers or going to the final step.

Coat all surfaces again with unthickened epoxy; when it is firm but not hard, put a coat of epoxy thickened to about thick cream or mayonaise again w/ colloidial silica, and fair everything as well as possible. Let cure at least 8 hours before stressing at all. This fixes the seal.

At the same time as the seal, you should be able to fix the upper hole. Grind it to a wide shallow dish shape; 12:1 is the recommended bevel. Cut a bunch of circles from your fiberglass cloth, starting at the full diameter, and progressively smaller. Coat with epoxy, working it into the hole as much as possible. Start adding the rings, squeegeeing off excess, epoxy, but not so much it starts to lose its transparency. Depending upon temperature, you should be able to get at least three thicknesses before they will start to sag out of place. Let these cure until they will hold in place well, and put on another three, etc until the hole is filled level with the keel surface. Again a coat of unthickened and then a coat of thickened to fill the weave of the cloth. Let firm up, after which you can use an epoxy-based fairing mix. After curing, fair to final finish. Underwater, epoxy does not need to be covered prior to antifouling paint, but does need to be thoroughly dewaxed.

If the hole in the bottom of the keel has stopped dripping, proceed as with the upper hole. If still seeping, try using a rolled-up piece of paper towel as a wick to pull as much water as possible. Bevel as above, then hit the hole with a hair dryer to both dry and warm the area. Using a hot mix of thickened epoxy, and with the hole warm, but not hot, shove the hole full. After cure, check to be sure water has not found a way around or thru your epoxy plug. If not, reinstate the bevel, and finish as above.

Be VERY careful about the blisters. Our Gulfstar 50 has had this class problem taken care of by taking all the fiberglass down to the core of the keel and then building her up with 15+ layers of fiberglass, gel and then two epoxy coats of barrier. No one knows for sure how the water gets into the keel but it seems that once it is taken care of the problem doesn't return.

I barrier-coated the bottom in 1992, and have had a few blisters since. I think most of the pre-1983 Gulfstars had a modest blister problem. In my case, before coating, I had probably 1000 blisters, only 2 of which penetrated the first layer of mat; all the rest were between the gel coat and the first layer. From what I have heard, this is fairly typical. I've not seen a GS hull that is actually damaged by the blisters.

I have owned my 1983 GS 36 for 15 years and love it more each year. I too sail on the Chesapeake and "Impulse" has weathered everything the bay could throw at her. She points well and handles heavy weather with confidence. When I originally bought her I had a blister problem. I had the hull peeled and then had the bottom reglassed and followed that with barrier coat and bottom paint. I have not had 1 blister since. All in all she is a great boat and and with a few hardware upgrades I would be confident to sail her anywhere.

... after three years of fighting blisters on our GS 50 it's time to bite the bullet - do a complete bottom job. ...

[Re: wet cement in GS 50 keel:]
If she has been out of the water for over a week, I would run a moisture meter over the bottom and assess how much drying will be required, not that it is a perfect science. But say the meter shows moderate readings, it will probably dry within weeks or months; if it shows off the scale, it will take longer and it is probably due to something inside the hull containing water such as the cement in the keel or water between the laminates, then it needs replacing. I would not know how to access the cement, mine is a fin, lead keel, I had problems with the core material in some areas below the waterline, the core was removed and replaced, yours [GS 50] is a solid fiberglass hull I believe.

Re: Keel delamination on 1975 Gulfstar 41 Ketch

Your keel is probably leaking due to breakdown of the well in the bilge under the engine. This was just filled with resine and no glass; the resine breaks down with time and allows bilge water into the keel box. You can check if this is the case by drilling a 10 mm hole in the part of the keel which is seeping. The delamination may be due to this internal saturation. The water will be heavily contaminated with bilge filth and does the GRP no good. I recently fixed mine by cutting small windows in the side of the keel at bilge height, removing the degraded resine and reglassing the bilge. Be warned if you don't correct this, any damage to the lower keel may lead to salt water entering the bilge. I experienced a very anxious time when my keel was damaged.

On my 1972 GS-36, I have drilled through the hull at several places and it is solid fiberglass where I drilled it. The bottom is solid. There is no blistering problem. Blistering seems to have been a problem of boats of many manufacturers that were made in the 80s because of mass production and not letting the hulls cure properly. In the earlier years of the fiberglass boat industry they had not yet begun trying to save money and the hulls were well made and properly cured.

The stanchions on my 1979 44MC are held in their sockets with set screws. The majority of these need to be replaced as they are mostly unmovable and quickly strip or split when I try to work them. I am very disconcerted with the way they are secured. Most are very loose and can be pulled up - those that I struggled to replace only hold by pressure and I see when the yard pulled the boat for the winter they pulled an entire section up in the process.

The first thing we did was to remove all of the set screws by whatever means necessary. Where possible, we drilled holes all the way through the stanchion and base and replaced the set screw with stainless steel bolts with stainless washers rounded to fit the circumference of the stanchion. This was secured in place with a lock nut. It does leave the head of the bolt and the lock nut outside the stanchion but, so far (three years worth) it hasn't been a problem. Where drilling through wasn't an option, we replaced the set screws with stainless self tapping screws. I have only had one of those present a problem. It was constantly backing out so I coated the threads with bedding and it hasn't been a problem since.

One tip: When drilling the stanchions and bases, we removed them from the boat and set up a jig on a drill press. That way you can control the alignment of the hole and it makes for a lot cleaner installation. The chrome on the bases is very slippery and it makes it very difficult to drill without imobilizing the bases.

> 1) Did you drill through one or both set screws?
Drilled through one.

> 2) Do you feel that compromises the integrity of the stanchion tube?
Tubes do not appear to be weakened. I've kept a close eye on them to watch for corrosion, wallowing of the bolts, etc. So far so good.

> 3) Do you recall what diameter hole and bolt size you used?
I could have used 1/4" but I didn't like the bite it took out of the bases. The 3/16" was just larger than the set screws.

> 4) If you removed the bases to drill, may I ask how they are attached?
> By that I mean that on our boat they are not all accessible (read none
> I've found) from the underside and I'm curious if there is a nut
> glassed in or if any attempt to loosen the bases will result in a
> problem I'd rather not tackle without serious time on my hands. I've
> always wondered this having wanted to remove them for various reasons
> over time - never had a leak - but I am a PM nut and would like to know.
They were attached with through bolts. Many were easy to get to, but some were real bears. Thank goodness for a small helper.

> 5) Out of curiosity - did you use a "nylock" or the all-metal style?
We used nylock.

I am looking for advice on a fix for replacement of the jib sheet track [on GS41]. The track must have been fitted before the deck was bonded to the hull. There is a cavity in the toe rail which makes fitting the new bolts a PITA as the old ones are hidden in this space. The deck hull GRP is irregular and I am not convinced will provide enough beef for the loading on the jib sheets.

I am thinking how to get the new nuts and washers to tighten against the toe rail moulding but have not come up with neat solution.

Any thoughts would be gratefully received.

Joint is too irregular to do a long backing-plate. Will fill cavity around bolts with epoxy, then through-bolt.

We have a GS37 so this may not be applicable to your situation.

Our jib track is attached with 4" machine screws that run through the track, through the toe rail, and then through the deck. This is extremely close to where the hull meets the deck (so close that one might assume the bolts are buried in the hull/deck joint). The nuts on the underside were covered with fiberglass.

At first glance one cannot see where the nuts are, but most show up as small bumps. I replaced six of these a month ago, and it required the removal of some inside cabinetry parts after which I also used a forstner-type bit to open up the wood frame just under the nuts. I then used a rotary burr on a flex shaft to grind away some of the "bump". This enabled me to go on top and drive them down using a pin punch. Where I had adjacent fasteners to replace - the spacing is exactly four inches apart.

The old fasteners might be #12 machine screws ... regardless I had to redrill the holes to accept a 1/4x20 machine screw. I used 4-1/2" long bolts. In one case I had to fill the area where the old nut was with some epoxy putty, but for most I just used a fender washer and nylock nut.

I did have one nut that was buried into the bulkhead between the lazzerette and salon. I "sistered" a bolt in a new hole close to the bad fastener.

Be careful not to tighten the new bolts too much - that can distort the jib track (learned the hard way). I used Life Caulk on the thread of the fasteners where they are in the teak, as well as under the head. I've wondered if the sealing with fiberglass was part of the reason the stainless fasteners failed.

I have found a cookery solution. I made baking paper piping bags, double thickness, which I attached to the nozzles used on glue/filler tubes. I found the best attachment was with masking tape.

Each hole 6 mm was then filled using the piping bag with a stiff mix of resin and microfibers. This mix needs to be stiff enough to stand on its own and yet still liquid. This results in a stalagmite which hangs to the upper surface. Using more than usual hardener the cone goes off quickly before it can collapse.

Now just drill through this cone which acts as a compression post.

The piping bags are cheap one-use so there is no mess.

I must say I am pleased with the result, which I will use again if I have a cavity to fill.