F-330SS Bulkhead Replacement
 

I have been monitoring a 'wet' bulkhead on my 1996 Formula 330SS over the past year. This bulkhead is the 'firewall' bulkhead, which separates the engine bay and the fuel bay. The high moisture level was discovered during the pre-purchase survey (in 2012) and the surveyor advised to keep an eye on it. Overall the boat was a good deal, so I went forward with the purchase and have been keeping an eye on the moisture levels.

I drilled some test holes in various areas of the structure to get an idea of the moisture levels in various parts of the structure. The problem area is in the center of the bulkhead, around the area where the center engine mount stringer attaches. The source of the moisture was from the fuel tank bay. I drilled a hole in the bulkhead and installed a thru-hull in that area to allow drainage. I pulled about 1 quart of water out of the fuel bay using a shop vac. I believe that the moisture is also propagating from the bulkhead into the center engine stringer. I have exposed some of the wet areas to see if I can get them to dry out. . . . That has only been marginally successful, as the center of the bulkhead remains wet. The wood is still fairly solid, and to head off rot, I have injected Ethylene Glycol into the wettest areas.

Here is a picture of the firewall bulkhead and the center engine mount stringer with some of the glass coating removed for inspection and to help the drying process.
http://home.comcast.net/~tpenfield/F...s/IMG_2048.jpg

I was able to get some moisture reduction, but since the boat lives outdoors, it really does not have a chance to dry out very well. So, now for 'Plan B' . . . I am thinking about replacing the middle section of this bulkhead so that the moisture does not continue to propagate throughout the structure. I know that there are a few folks on this forum who have done some bulkhead and stringer repair on their Formula's over the years. So, I wanted to get some inputs on my plan of work.

Using my 1990's "CAD" software, I have created a drawing of the structure of my 330SS. The main bulkhead is shown in blue. The wet area is the orange hashed area low and centered in the bulkhead.
http://home.comcast.net/~tpenfield/F...330WF4600X.jpg

I plan on cutting out the center section of this bulkhead and removing it. The section to be removed goes right up to the main stringers that are along side the fuel tank.
http://home.comcast.net/~tpenfield/F...330WF4601B.jpg

Then I will have access to the fuel tank bay, where I can remove some of the foam from behind the tank, inspect the butt end of the tank, etc. There is about 6" of foam between the tank and the bulkhead. So, with this area cleared out, I will have room for tabbing in the new bulkhead.
http://home.comcast.net/~tpenfield/F...F330WF4602.jpg

There is a spacer/stiffener for the bulkhead (shown in Yellow) that I will probably leave in place, unless it seems to be in rough shape once I expose it. After a bit of grinding the tabbing contact areas, I will make and install a replacement of this bulkhead section.
http://home.comcast.net/~tpenfield/F...F330WF4603.jpg

In order to get the tabbing installed on the 'blind' side of the bulkhead section, I will probably need to drill a couple of 4" holes in the new bulkhead on both sides of the center line. Then I can install a deck plate in those holes. I will probably keep some sort of drain for the fuel bay, but give that drain its own 'mini bilge' so that the engine bilge water does not find its way up into the fuel bay. (See below)
http://home.comcast.net/~tpenfield/F...inage-Dam1.jpg

I am hoping that replacing the bulkhead section at this time will avoid more significant work in the future. I had to do some similar work a while ago on my 242SS, but that was a single engine and a much smaller boat. Just looking to get any input from folks who have done a bulkhead or stringer repair on a twin engine Formula.

I will probably do the cutting work a week or so after the Thanksgiving Holiday (USA), and let it sit until until Spring 2014 to do the fiberglass work (3-4 months).

I'll post updates as I go, but for now looking for any input, comments, ideas, gotchas.

T.I.A.

wow kudos to you for taking this on, and your cad drawing very cool, will follow you along, hope it goes well

Only advice I'd give is to make sure it's REAL dry before you begin. Locking any moisture in could just make the problem continue to get worse.

Looks like a challenging project. Good luck!

Dave

It is a PAIN IN THE AZZ!!! After doing it on my boat I don't know how it can be done properly with out removing the last foot or so of the floor. You need to be able to tab the the ouside of the stringers as well as the inside. I don't think a 4" hole is going to do the job. You have to round over the inside edge before you glass and doing that blind will be super hard if not impossible. It sucks because you start to get into all the "may as wells". You know while I have this ripped apart I may as well go a little farther… I glassed mine up on both sides before I put it in the boat. That way I knew I had a real good bond of the glass to the wood. Then I removed the entire floor of the boat and re tabbed in the thing. Then I poured in new foam, put the floors back in (oh ya had to re-core them as well because they had delaminated) and then got it all back together. It can be a never ending excavation project…

Thanks for the cautions and advise, Audiofn. IIRC, you have a thread (or 2) on your rebuild work, so I'll search those out. I figure that if I map out a game plan, I can (hopefully) avoid many of the "may as well" items. I did a bit of that when I had to do the bulkhead on my 242. Ended up replacing the fuel tank, adding a secondary bilge pump, etc.

I plan on making my cuts of the bulkhead just inside of the main stringers, so that the outside tabbing of bulkhead-to-stringer will remain intact. I might have to overlap the bulkhead in that area where the new section of bulkhead joins the existing section. We'll see how that goes . . .

I have been trying to 'avoid' doing this 'project' by seeing if I could get the structure to dry out. But, without a heated indoor place to store the boat over the winter, it does not seem to be happening. As much of a PITA that this will be, I am hoping that it will prevent more extensive work in the future.

My game plan is to start cutting on the weekend of Dec 7-8th, so I still have some time to anticipate the 'fun'.

The water will go a lot farther then you expect! Even if you have a dry area it would take for ever for it to dry out if it ever would. Best thing to do is to do what you are and cut it out. Just realize that the wet area is going to go a LOT farther then you think unless you are lucky. Keep us updated when you get started!

Understood, wood is like a sponge, so I know that the moisture has traveled a bit already. It is something that I will continually have to monitor, even after I replace the bulkhead section. I probably should get a professional grade moisture meter to make an annual inspection easier.

just so you know this is a common problem on the 28 ss 33 ss and the 336 sr1 boats
their is 3 in my area and all have the same issue

Yes, probably a lot of boats have the moisture issue in the bulkhead, yet remain unknown. It seems that the problems are related to the fuel bay accumulating moisture . . . the lower part of the foam retains the moisture up against the bulkhead . . . The moisture then makes its way into the wood core and migrates outward towards other structural components. This process takes many years to play out.

I contacted Scott Smith at Formula about the issue, when my 242 bulkhead had the same problem, just to get some guidance on the corrective actions to take. I'll apply that same advice here as well.

It would seem that it is not an issue exclusive to Formulas though, any boat of similar design could have the same issues.

If I ever get to working on my 302 again I plan to put a way for water to move around a little more freely. You can't possibly keep it out 100% so I am going to let it go in under the tank and then back out. I have not figured out how to do it 100% yet but I have some ideas I have been running through my head. This will allow water that may get up in the cabin or anyplace along the deck to just run down and out the bilge…. Like I said not sure how I am going to do this yet. Or I may change out all the inspection plates to water proof ones and glass the floor in place so that it is in fact water tight...

Yea, I looked through your 302 thread, but did not see that you finished. I did that same sort of thing, as far as giving water an escape route, when i did some structural work and fuel tank replacement on my 242.

I installed a channel under the tank. It is 'rounded corner bead' stock that I got at Home Depot.
http://home.comcast.net/%7Etpenfield...s/IMG_0472.jpg

And also provided some space behind the tank for inspection and drainage.
http://home.comcast.net/%7Etpenfield...s/IMG_0593.jpg

I am thinking of providing an area of inspection/drainage space behind the tank of my 330 as well, when I install the new bulkhead.

It is that way stock on my 85. Found out the stupid way early in my ownership of it. Wanted to clean the bilge in the engine compartment, and thought a good way was to flood the area with soapy water, pull it around for several miles, including one stop sign at the bottom of a hill, and then pull the plug and drain the soapy water, leaving behind a shiny clean bilge. Well, it takes a lot of time and effort to remove the soapy water from the cabin's carpet. And at that point I really didn't care about the dirty engine compartment either.

Point is there is free movement for water past the fuel tank on an 85 302. And it is not always a good thing.

Formulas have drainage from the cabin to the engine compartment that bypasses the fuel bay (via a 1" tube).

There should be a plug for the drain up in the cabin bilge to prevent the back flow if engine bilge has a fair amount of water in it.

What seems to be lacking is drainage of some sort for the fuel tank bay, so water collects in there.

Update:

Today was bulkhead cutting day. I got a fair amount done, but there is still some more to go. Here are a few pictures of the day . . .

Adding some support to the hull in the area of the bulkhead

http://home.comcast.net/~tpenfield/F...s/IMG_3178.jpg

Taking all of the fixtures and fasteners off the bulkhead to loosen up the wiring and plumbing. I drilled a starting hole for the sawzall on the port side, right next to the stringer.

http://home.comcast.net/~tpenfield/F...s/IMG_3187.jpg

I cut the bulkhead out in 3 major sections (upper, port, starboard). There is the upper and the port side removed.

http://home.comcast.net/~tpenfield/F...s/IMG_3212.jpg

Here is the starboard side removed.

http://home.comcast.net/~tpenfield/F...s/IMG_3214.jpg

I still have a bit more cutting to do, but that was all of the time that I had today. The lower bulkhead sections were really wet, so I'm glad that they are out of the boat now.

I also made a couple of videos of the work, etc. . . .

http://www.youtube.com/watch?v=bXLkQo_TRxs I probably won't do anything more until after the holidays.

Here is an additional video from the day.

http://www.youtube.com/watch?v=3dXMNJ5j2gY

Very cool to see you posting videos, Ted! Makes visualizing the work much easier for us. I'll be checking in often. Good luck.

Thanks, I am hoping things go somewhat according to plan, but there are usually some surprises once you start opening things up.

I have been thinking about the two 'discoveries' that I made while cutting out the bulkhead on Sunday.

(1) Bare wood on the hidden side of the bulkhead . . . and . . .

(2) the void in the foam on the port side, up against the bulkhead.

These 2 issues seemed to have worked in combination resulting in the 'wet' bulkhead after 15+ years of the boat's life.

I figure that the moisture that collected in the foam would tend to condense on the surface of the void area, and then have a downhill path to the exposed wood surface of the bulkhead as pictured below.
.
http://home.comcast.net/~tpenfield/F...-330-Foam1.jpg
.
You can also see a glimpse of the fuel tank in this picture (gray triangular shapes). So, it will also be interesting to see if moisture was trapped up against the tank surface.

So, it looks like a combination of issues can lead to problems after 10-15 years of a boat's life cycle. If the foam did not have a void . . . or . . .if the bulkhead had been fully glassed, then the moisture problem may not have happened at all. . . or be much more minimal.

a quick update:

I might get another day of work on the boat before the Christmas & New Year's holidays. Meanwhile, I have been wondering about one aspect of the structure . . . in terms of how the cockpit liner (assembly) and the stringer grid are mated. From what I can tell the cockpit assembly makes contact and is supported by the stringer grid only in a few areas shown by the red lines in the drawing below.

http://home.comcast.net/~tpenfield/F...ntactAreas.jpg

However, the cockpit sole merely rests on these contact points, it does not appear to be bonded or anything like that. Here is a close-up of the contact point along the starboard stringer

http://home.comcast.net/~tpenfield/F...s/IMG_1045.jpg

No tabbing or adhesive that I can see. The other contact/support areas are the same way. My 1991 242SS was also the same way, - the cockpit sole merely rested upon the stringer grid. On the 242 it was more of a flat surface and was symmetrical - port & starboard. The 330SS seems to be just the top edge of the stringer and bulkhead grid.

Anyway, have sent a note to Formula regarding the contact points and to ask if there is any advantage/disadvantage to bonding the cockpit sole to the stringer grid where they make contact. I just wanted to see if anyone else who has dug into the structural depths of their Formulas has noticed this aspect of the boat and has modified it or anything. :)

A Factory tour would work

It would be nice . . . I am wondering if I would have to buy a new boat from them first ?

I did send Scott Smith (at Formula) a note regarding the cockpit sole & stringer grid bonding question. so, we shall see what becomes of it.

I am thinking I might just tab the contact areas to the stringers and then fill the space between the hull and the stringer grid with foam to make the boat stiffer and give it more flotation.

Nope, they will treat you as new

It is a wonderful tour, and they are top notch hosts.

I got word back from Formula Tech Support today. They were aware of this thread that I have going on. . . :cool:

Anyway, they indicated that I could stiffen the boat up, but it really was not necessary. Bonding the cockpit sole to the stringer grid may cause the cockpit liner to flex in some areas that it normally would not. So, I will take their advice into consideration in anything that I do as part of the bulkhead repair.

Great manufacturer involvement, now if they could only tell me how to turn mine into a 38 for under 10K:whistle::whistle:

Something like that I would leave as is. It has lasted how long the way it is? Unless you see anything that would cause you to think there is damage happening then your "fix" could cause other problems. I think that is what Formula was saying as well.

When you cut out your bulkhead were you able to check the stringers as well? Often times the water can go from the bulkhead to the stringers and on and on and on. That is what happened in my boat. When I did the new stuff I was able to compartmentalize things. So if I do get one area wet it can not travel to another spot on the boat.

The only thing that I see as a possible issue with the cockpit floor is some crazing of the gelcoat near the step that leads to the cabin.The surveyor indicated that it is usually caused by something 'hard' below it. So, that may be the effect of the stringer grid contact point and any 'pounding ' effect when the floor & grid quickly separate and come back together as the boat flexes. That is the only area that I see a negative effect f the current configuration. I will have to take a closer look at the contact point and the crazing, etc.

I did not get a chance (yet) to inspect the lower portion of the main stringers. That will be part of my next steps, once I remove some of the foam from the rear of the fuel tank. The upper portion of the main stringers look fine . . . nice blond encapsulated wood. Once I open things up a bit in the fuel bay, I can probably drill a couple of test holes in the stringers to get a direct moisture reading on my meter.

Port Stringer (upper portion)

http://home.comcast.net/~tpenfield/F...s/IMG_1105.jpg


Starboard stringer (upper portion )

http://home.comcast.net/~tpenfield/F...s/IMG_1110.jpg

I will definitely isolate the new bulkhead section (by encapsulating it in fiberglass) from the rest of the structure, just so moisture can not propagate to other structural members. I did that sort of thing when I replaced the bulkhead on my 242SS.

I'm also hoping that the exposed wood edges from the bulkhead cut will dry the remaining portions of the bulkhead out a bit. however, I may have to put a heat gun to the edges for a while, since the boat is out in the cold of winter and not much will evaporate in those conditions. I probably won't get to work on the boat again until the first weekend of 2014, so we will see how things look at that point. It will have been about 4 weeks since I cut the bulkhead section out.

Winter Update:

I removed the foam from the rear of the fuel tank today. The weather had been quite cold over the past few days, so some of the foam that was holding water was actually frozen. I found that the water seemed to have penetrated parts of the foam, in "veins", rather than spreading evenly across the lower portions of the foam.

Here is a picture of a fairly isolated water 'vein' the I found on the starboard side.
http://home.comcast.net/~tpenfield/F...s/IMG_3331.jpg

It took a few hours to pry most of the foam loose from the rear portion of the fuel bay, exposing the butt end of the fuel tank and the last few inches of the main stringers. The fuel tank looked pretty good . . . As expected, I did see some darkness (i.e. moisture, etc) penetrating the main stringers, but it looks like it is in a fairly early stage. So, I may try some 'chemotherapy' to the stringers. Pictures below . . .

Starboard side:
http://home.comcast.net/~tpenfield/F...s/IMG_3344.jpg

Port Side:
http://home.comcast.net/~tpenfield/F...s/IMG_3348.jpg

I also made a video of the day . . .
http://youtu.be/BUFlkiYYIc4 Next steps will be to clean up the cuts and to apply some treatment to the main stringers. I probably won't be able to do too much more for a few months, unless there is a winter thaw . . .

A couple of follow-up questions from what I found when I removed the foam . . . just looking for any thoughts or ideas on a couple of things.

1) The darkness that is starting in the main stringers: My plan is to let things dry out a bit, then 'inject' some rot preventative liquid into the stringer at the darkened areas. Two types for rot deterrent liquids come to mind; Bleach or Ethylene Glycol (Green antifreeze) . . . any preferences or rationale of one versus the other. Any additional thoughts?

2) The separation of the foam from the sides of the fuel tank: I'm thinking that this should be remedied in order to prevent water from being trapped between the foam and the fuel tank. I was thinking that I could inject either more foam into those areas or perhaps inject an epoxy of some sort to re-bond the foam and fuel tank. Worst case is that I would have to remove the tank and re-foam it. Any thoughts or ideas on the fuel tank/foam bonding?

Thanks for any thoughts or ideas on these items.

This is one of the many, many reasons we stuck with Formula when we upgraded. The factory support has been absolutely top notch. When I had my 20 year old 303, they treated me like I was a brand new 382 customer. Their enthusiasm for the brand as a whole, not just the latest and greatest is awesome.

We have visited them and the Miami show, and will again this year. Although a new build was out of budget this go around, I honestly think if we ever build a new boat it will be a Formula.

It would be kind of cool to get a small group together for a tour. Every time I speak with them they always extend the invitation to visit.

Sorry to de-rail your thread... great work, and I'm enjoying all the pics!

Fuel tank
 

what about expansion room??

Yes, awesome support of their products regardless of being the original owner or not. Would like to buy a 292 brandy new some day . .. . Maybe some day. :)

They have already helped me a couple of times on this boat and were also helpful with my 242SS. When you think about it, supporting the used boats helps create a market for the new boats.

Regulations for aluminum tank installation require that the foam remains bonded to the tank walls and that the bond needs to be stronger than the foam itself . So, it would not be 'expansion room' by design. It seems that the bond of the paint to the aluminum was not strong enough and gave way.

I am now thinking that my best approach would be to pull the tank, inspect it, re-paint it and then re-install it. That way, I could see if there are any corrosion issues from the trapped moisture and remove the old/wet foam and replace it with new foam.

I would pull the tank out for sure. You've come this far, no reason not to inspect and repaint while you're in there.

For your question #1. I would drill into the area and see how bad it is. Of course now with everything frozen you may need to warm it up to see how bad it is. There is NO WAY I would ever inject anything liquid in there. If you inject it in there then how is it going to get out? If you find it is rotten then cut it out! Remember water expands with horrible results as it freezes. Only way to stop the damage is get it 100% dry. If you only have access to one side of the stringer you could very carefully router out the area that is soft. Be very careful to set the depth so that you do not break through the glass on the other side. You can then put a new piece of wood in there and then glass it back in. That would guarantee that it does not get worse.

#2 Try and figure out how bad the separation is. The issue you may have is that if your tank is as bad as mine was it will be covered in oxidization. There is not way to get the foam to bond to the oxidization. So IMO the only way to fix that 100% is to cut back the foam enough that you can sand off the oxidization. I used a chainsaw to remove the foam.

Thanks, Audiofn. I will exposed the darkened wood areas on the stringers.. I have a feeling that the wood is still hard, just black. That's how it was on my 242 repair. Even in a 'blackened' state the wood was really substantial and put up quite a fight to get it out. So, I'm wondering if I will be able to expose the wood, treat it with bleach or EG , let it dry out and then seal it all back up with glass, etc. Probably won't know until I expose the darkened areas.

As far as the fuel tank. I have pretty much decided that I should pull the tank, inspect it, re-paint it and then re-install it. The areas of the tank that I have exposed so far look very good, so unless the underside or other areas are dramatically worse, then I should be OK with the tank. It looks like I have to take out the dual helm seat assembly in order to get full access to the deck hatch and remove it. that will expose the fuel bay. The waste tank is suspended over the fuel tank, so I'll have to take that out as well.

Then if the foam is really separated all-around, the tank should pretty much just lift out. another benefit of removing the fuel tank (and the foam) would be that I can easily tab the new bulkhead from the inside, rather than having to cut access holes and install deck plates in the bulkhead.

Anyway, my next opportunity to work on the boat may be MLK day (Jan 20th), hopefully the cold weather will have subsided a bit by then. I'd like to get as much work done during the winter months, because I am usually in a time crunch with regular prep work in the Spring time (April - May).

I hear ya with the cold! This is cold for even Boston… Looks like it is going to moderate soon!

A Quick Update:

My next opportunity to work on the boat will probably be the MLK Day holiday this coming weekend. My plan is to shift my attention towards removing the deck hatch in the cockpit sole in order to expose the entire fuel tank bay. I will need to disassemble and remove the dual helm seat so that I can get to the deck hatch.

Once I have full access to the fuel tank bay, I can check the entire perimeter of the tank to see how much of the foam has separated from the tank. I suspect it may be quite extensive, given that it appears to be an issue with the paint adhesion . . . unless the paint adhesion issue is localized.

Anyway, I'm not sure how much of the dis-assembly work that I will get done in one day, but we shall see. Temperatures have been above freezing during the day for about 1 week, So, the 'frozen' foam may be thawed out by now.

Helm Seat Removal:

I spent some more time yesterday working on the boat . . . got the helm seat removed and opened up the deck hatch to view and inspect the fuel tank bay. The helm seat covers the forward starboard corner of the deck hatch, so it has to come out.

First the helm seat:

I found some documentation on the Internet on how to remove the helm seat. There are some screws located under the cup holders that hold the seat assembly to the sidewall. The screws merely hold the seat assembly down onto two retaining clips.

http://home.comcast.net/~tpenfield/F...s/IMG_3482.jpg

http://home.comcast.net/~tpenfield/F...s/IMG_3486.jpg

Then there are 4 bolts on the base of the seat. There is also some wiring for courtesy lights that gets disconnected.

http://home.comcast.net/~tpenfield/F...s/IMG_3483.jpg

Once the screws and bolts are removed, the seat assembly pulls away from the floor and wall of the cockpit.

http://home.comcast.net/~tpenfield/F...s/IMG_3493.jpg

I turned the seat assembly on end just to see if I could further disassemble it in order to get it out of the boat in several pieces. I would estimate that the seat assembly weighs 250-300 lbs.

http://home.comcast.net/~tpenfield/F...s/IMG_3496.jpg

After a while, I found a way to separate the seat portion from the backrest and base assembly, making it more manageable to remove.

http://home.comcast.net/~tpenfield/F...s/IMG_3499.jpg

So I was able (barely) to get the helm set out of the boat in two pieces.

Here is a video of the day, starting with the seat removal:

http://www.youtube.com/watch?v=VnHX6sj9B7w I have the seat pieces stored in the garage for the duration of the project. With the seat assembly removed, I could now start to remove the deck hatch, which would expose the fuel tank bay.

Deck Hatch Removal:

Once I had the helm seat out of the boat, I could fully access the deck hatch. It covers most of the cockpit floor.

http://home.comcast.net/~tpenfield/F...s/IMG_3508.jpg

There are screws and caulking that hold the deck hatch into place. So, it was a matter of unscrewing everything and cutting the caulking.

http://home.comcast.net/~tpenfield/F...apeimage_1.png

After the deck hatch was unfastened, I lifted the hatch from one side. It too was fairly heavy, more so that I was hoping for. I will have to get a helper in order to lift it out of the boat.

http://home.comcast.net/~tpenfield/F...s/IMG_3511.jpg

However, with the fuel tank bay exposed, I was able to get a a better look at the tank and the foam adhesion. The front face of the tank seemed to be in fairly decent shape, in terms of the foam and paint adhesion. The foam did not pull the paint off of the tank. However on the port side of the tank, the paint came right off with the foam, as I removed some pieces.

http://home.comcast.net/~tpenfield/F...s/IMG_3519.jpg

The port rear corner of the tank had a visible and fairly large separation between the tank and the foam. It looks as though the foam has shrunk in that area, puling away from the tank and creating the gap that you can see in the picture below. There was also similar evidence of separation on the starboard side.

http://home.comcast.net/~tpenfield/F...apeimage_2.png

Here is a video of the deck hatch removal and preliminary inspection of the fuel tank bay and the foam adhesion:

http://www.youtube.com/watch?v=-naizJCrJpE At this point it is a matter of seeing how easily the tank will come out, given that it has separated from the foam at the rear and along the sides of the tank. First, I will have to remove the waste tank, pump out the few gallons of fuel that remain in the tank, and disconnect the hoses and wiring.

It will probably be a couple of weeks until I can get back to it, as I am heading to Florida for a few days . . .