Another Used Boat Victim, Stringer/Transom Rot

[CrownlineRider92]

Hey guys,

Long time reader, first time posting a topic. I am looking for some opinions.

About a month ago, I purchased my first boat. A 1992 Crownline 196BR with a Mercrusier 350. Overall, the boat looked to be in great condition. The previous owner always garage kept it and had lot of paperwork of work done to the boat from a reputable boat shop. Motor was rebuilt and the boat as a whole only has 370 hours. Mechanically everything is perfect, and the interior was also in great shape. The Vinyl is still soft, no rips, tears or rot. The exception being the right bow seat. The floor even seemed to be very solid and the paint/haul was in extremely good shape. I thought I got a pretty good deal...until last night.

Yesterday after washing and waxing the whole boat I decided to shop vac the interior. I opened the ski hatch to find moisture on the carpet in the bottom. I removed the carpet only to find the stringers to be rotten. When pulling out the carpet, some of the fiberglass casing even came off with the glue used to adhere it. After further inspection, I found about half of the stringer (bottom up) is rotten and the top half of the stringers are solid.

This rot then had me concerned about both the transom and motor mounts. Using a hammer, I tapped on the back haul of the transom and can here a dull thud to the right of the out drive.....This means at least part of the transom is rotten (suspect 1/4 or less).

Lastly, I have read on forums that you can check the motor mounts by trying to tighten the bolt and see if they free spin. When I tightened the bolts, they seem to have good bite into something. With that being said, there is a white silicone like epoxy around the bolts. I would not be surprised if the motor mounts have been pumped full of epoxy as a "fix".

Now the question is what should I do next? I spent $5, 000 dollars on what I though was a lake ready boat. Mechanically the boat runs flawlessly, engine fires right up every time and runs strong. (Boat will run 62 mph with 2 people) The interior is also in great shape, minus the bow seats. Overall, it's a sharp looking boat aesthetically. But the bones of the boat are weak and brittle.

I figured I have two options: Either bite off a huge project and fix it and make it a boat I will have for years to come, or sell it and find something else. I believe I have the capability to take on this project, but it will push me out of my comfort zone. I am very knowledgeable when it comes to the mechanical side of things (I have a B.S. in Mechanical Engineering) and work on vehicles on the side. But I am no expert when it comes to carpentry and fiberglass.


If I would take on this project, it would not be until winter. Is it safe to expect that the boat will make it through this summer without causing catastrophic damage? I do not want to put myself or others I have on the boat at risk. I have had the boat out three times already this year and it seems to be solid, but I am now worried with this newly found discoveries.


Please share your thoughts and experiences! Thanks for your time!

 

[Woodonglass]

Welcome to iBoats!!!! You've come to the BEST Boat Restoration Forum in the World!!! Best Help and Most Knowledge anywhere...anytime!!!

The Stringers, Deck and Transom ARE the structural components of the boat. When they are rotten then the structural integrity of the entire boat is compromised. Big Waves and wakes hitting a hull with weak components can and HAS caused catastrophic incidents. I'd recommend NOT taking this boat on the water until the structural components have been properly repaired. We have MANY examples such as yours where our members have supposedly purchased "Lake Ready" boats only to find the same issues you have found. Most of them have bit the bullet and made the repairs. With the expert advice you'll get here on the forum I'm pretty sure you'll be able to have a Great Restoration and be ON THE LAKE next season. Check your motor mounts by drilling holes in them with a 3/8" bit. Drill down low and check the shavings. If wet and dark, Bad News!!! if Light and Dry fill the holes with sealant and carry on.

 

[tednv]

if I ever have to do a full re-deck and transom repair I will use hdpe sheet instead of plywood. it's heavier than same thickness plywood but you don't have to use the same thickness to achieve the same strength. It will never rot and deform. I did some deck work on my 99 bayliner recently, nothing too major just fiberglass the top, epoxy layer, recarpet and replace the ski locker hatch. The hatch was made out of that great expensive marine grade plywood everyone talks about. Underneath it did have a layer of epoxy paint that held up ok except for a few cracks, but the sides had nothing, just bare wood. The carpet wasn't looking too good so it started out as a recarpet project, but then after pulling carpet i noticed that the deck wasn't fiberglassed (only in front bow section) so a lot of the paint just came off with the glue. I decided to lay down 3 layers of fiberglass mat followed by a thick layer of epoxy. The ski locker compartment often gets a little water in it that gets trapped and pushed up into the plywood hatch when it evaporates and condensates. The hatch itself felt so flimsy and I was always afraid to step on it because it creaked and felt like it was about to break. Horrible. I threw away the old hatch and bought some hdpe sheet to make the new one out of, it was slightly heavier but turned out beautiful and I will never ever ever for as long as I'm alive have to do anything to that hatch again. I hate plywood/fiberglass with a passion, they might as well use cardboard and fiberglass it would probably work just as well. So sorry to hear about your experience though, and I'm sure you already know the answer to your question about the boat being safe for just another season

 

[Woodonglass]

HDPE is not a good choice for structural components in a boat. It has NO structural strength and neither Poly Resin nor Epoxy resin will adhere to it. This topic has been greatly debated here on the forum by numerous knowledgeable boat builders. There ARE several composite materials that ARE suitable for boats but...HDPE is not one of them. Properly encapsulated plywood is More than adequate for restoration uses and will last several Decades if properly maintained, but, IF someone wants to invest the extra money into composite materials then that's fine too. IMHO using these High Costs materials on a Boat that more than likely you won't own in 10 years is a waste and cost/benefit ratio is low. But I AM just and Old Dumb Okie so there is THAT to consider!!!!

 

[CrownlineRider92]

Thanks for your quick responses. As this was not the answer I hear, it was what I expected. Nobody is gonna tell me its is safe and take on that liability. My question is now is how many boats are out there running with rotten transoms and stringers without the owner knowing any better? From the reading I have done, any boat over 15 years old has 90% chance of having rotten stringers.

I understand the importance of the stringers/transom for structural integrity of the boat but at what point would failure be expected? 75% of the stringers completely rotted?

I figure whats left of the stringers and a solid floor would provide enough integrity temporarily.


Idk, I may be in denial and still trying to see the glass half full instead of half empty.

 

[Woodonglass]

Don't want to yank your chain and Of course you KNOW you're right but... you also KNOW your boat has problems. You can't use ignorance as an excuse if something did happpen. No one can tell you how safe or Un-safe your boat actually is. All I KNOW is I wouldn't ever put a boat on the water with anyone that I care about on board, unless I felt I had done everything I could to ensure their safety. Anyone who has any doubts about their boats structural integrity, is obligate, IMHO, to inspect it thoroughly and take action on the issue. This can include retiring the boat from active use. Denial is NOT just a river in Egypt!!!!

 

[CrownlineRider92]

Thanks for your honest opinion Woodonglass. Definitely putting things in perspective and I value your input. I only state what I have read to help me understand the integrity of these boats in my head. Just sounds like there are a lot more people out there in risk other than me.

 

[Woodonglass]

I heartily agree that the probability that there are numerous boaters on the lake in potentially unsafe boats, is pretty HIGH!!!!
The question is...Do you want you and your family riding in one of those boats??? Heck, even NEW boats can have catastrophic events occur. It's always a RISK. I just try to minimize those risks as best I can. Bottom line is...It's your boat and you're free to do with it as you see fit.

 

[Baylinerchuck]

Thanks for your honest opinion Woodonglass. Definitely putting things in perspective and I value your input. I only state what I have read to help me understand the integrity of these boats in my head. Just sounds like there are a lot more people out there in risk other than me.

You are absolutely correct in your statement. Most people either don't know enough to realize their boat is rotten or don't think it's "that bad", or don't care. The majority of the boats out there 1995 and older are fairly apt to have issues. No one on this forum is gonna tell you to go have fun another season given the information you posted. That's your decision. I can tell you my Chap was plenty rotten, the PO used it that way, and I used it one season that way. Check out my restoration link still in process. Honestly my whole restoration started the same way you describe. Carpet in the ski locker. Wet stringers. Wood pieces here and there. Next thing you know I'm gutting a boat. If you do decide to use it one more season, just take it easy........

 

[tednv]

No Title

yeah, I've had a part in those earlier hdpe is no good for structural stuff discussions before I decided to go ahead and use it for some structural stuff anyway

this is me on 1/2 thick leftover piece of hdpe, standing on a 3" wide section on one leg (sorry for hairy legs, i'll shave next time)

as you can see it bends a bit with 240lbs on it but after I get off it's straight again. try that with a piece of 1/2 plywood, i doubt it'll still be in one piece. I did this test on this exact piece in this exact spot multiple times

I used it to build a new hatch and to replace some of the rotten 5/8 plywood strips that go under the deck to reinforce hatch seating surface

I made a hatch out of 5/8 hdpe, which was overkill, 1/2 would have worked just fine

as for adhesion, 5200 sticks to it just fine and you can put as many stainless screws into it as you like without having to worry about sealing the holes

what I ended up doing for those reinforcement strips was use a router to run a bunch of channels through it first even though I could have just sanded the surface with rough paper and it would have had better adhesion than what plywood will have after it absorbs a little moisture

 

[Durango318]

Wow bummer!
I've been there too. Some things I'd like to pass on. Most likely you have only found half of the rot and you will find the rest as you start digging. It's always four times as much work as anticipated. There are no short cuts, injecting Git rot is fine for small non critical areas but not engine stringers or transoms. Large masses of epoxy or polyester without the fibers of glass or wood cellulose is hard and brittle, think hard candy. Smiths penetrating epoxy is not the answer in this case either. Any epoxy that has volatiles to thin it will not cure properly if injected into something that has a covering like paint or glass that keeps the volatiles from evaporating out. It ends up like Jello. Note: You can apply epoxy on polyester but never polyester on epoxy. You can keep adding new layers epoxy glass before it sets up but once it hardens, to add more layers you need to clean and scuff the surface because curing waxes and oils form on top. Xylene is a great cleaner but toxic, use protection. Epoxy is much stronger but much more expensive than polyester resin. West Systems has never failed me.
The transom is the biggie and most critical on a stern drive. Most likely it wont fail in your case from load(yet) but should you strike bottom or an object the whole drive could be ripped off leaving a huge hole in your boat.
How big and how deep is the rot? Get yourself a cup of coffee (helps me think) and drill some test holes just through the glass layups so you can probe with a pick and feel if the wood is gone or just delaminated. If delaminated you could drill a pattern of holes and inject Git rot or slow un-thined epoxy. If it's rot, the wood has got to come out. SORRY
Yes you may have to remove the engine and drive to do it it right, that is if you are going ahead with it and feel it's worth YOUR labor, aches and pains . It's not a one weekend project. If you pay someone to do it, it may cost more than the boat it worth.
Don't forget to hunt down where the water got in or the rot will be right back.

 

[tednv]

No Title

almost forgot, final product. it feels way more durable than the 5/8 plywood it replaced. carpet adhesive, contact adhesive, and 5200 stuck to it really well (unsanded) but I added the grooves to the strips just in case. and again, I will never ever, for as long as I'm alive need a new hatch for this boat

having rotten transoms is why most boats end up at the junk yard and there's absolutely no reason to use plywood if you're not a boat maker trying to sell more boats. hell, I'm surprised they're not using mdx instead of plywood yet, that would help boost sales even more

I do appreciate the feedback though, I think hearing all the reasons for why it wouldn't work helped me find a way to make it work. Luckily my transom is still ok and the deck is still good. when it's time to redo it, out will go the plywood and in will go the 1/2 hdpe and not just for the deck but for the stringers and transom too (obviously thicker blocks)

I have no problem with the extra cost either, if it means doing it once and never ever having to worry about it again, works for me

 

[tpenfield]

If there is a concern about using wood, then the structural foam boards (Divinycell, Coosa board, etc.) would be a good choice, but expensive.

CrownlineRider92 , your story is very common as WoG stated. Paying good money for a boat that looks good on the outside, is in mechanically good condition, previously owned by a meticulous person, and yet . . . the boat still rots from the bottom up. That's what boats do, and the TLC that a previous owner may give it, does not do anything to stop it.

No one can say for sure how structurally sound the boat is at this point. As a mechanical engineer, you will know the value of a solid structure for the hull. The hull itself is very wobbly without the structure.

As far as options . . . fix or sell. If you were to sell the boat, how would that work? Cover everything up and don't mention it? . . . or sell as a fixer?

As far as fixing the boat, check out Baylinerchuck 's thread, as your boat is pretty similar to his, and he is doing a very good job in making sure the wood structure is sealed up. As mentioned, there are many, many threads of restoring same/similar boats for you to review.

Plan on about $2000 in materials and a few months time of weekends and evenings to gut the boat and rebuild the structure. Fiberglass is pretty easy . . just cloth that is soaked in a liquid that turns into plastic.

 

[Scott Danforth]

tednv, HDPE is not a valid marine structural material. PERIOD. for hatches, you could use it, however not for floors, stringers, transom or anything structural

and no, 5200 will not stick to that any more than it sticks to delrin or UHMW PE.

you obviously dont understand how plywood works, or how recycled soda bottles become HDPE. place your HDPE in the sun for a while and you will get permanent deformation.

So please, quit hijacking CrownlineRiders thread

 

[ezmobee]

I'm sorry that this happened to you. Definitely a nightmare. The "good" news is that $5k seems pretty cheap to me for a non-beat 19' with a rebuilt motor. I think even if you put $2-3k into a rebuild, you'd still not a have too much money into a now solid-for-life 19' with a rebuilt motor. It's probably worth doing. Especially since you'd have to sell this one and prolly need to sheel out $10k+ for a more-guaranteed-not-to-be-rotted replacement. Friscoboater's SeaRay youtube videos and Baylinerchuck's restore thread are excellent resources.

 

[CrownlineRider92]

Thanks for all your guys comments. I have already watched all of Friscoboater's SeaRay restore on Youtube and feel like he does an excellent job showing all that is involved in the project. For the time being I will be doing a lot of research and preparing for this project. I appreciate recommendations on similar builds and will review them closely. End the end, I want a boat that I will not have to worry about the structure integrity for years to come. I am even considering doing a fiberglass floor of some kind with a snap in carpet

As I am kinda upset that the boat is in the shape it is, I can only look at it as a learning experience. I have a lot to learn in the upcoming months. The transom rebuild intimidates me the most. Please share any additional resources I may find helpful such as fiberglass DIY, what type of fiberglass/resin to use, ext.

Thanks for all your guys support on this topic. I really value seeing different sides and options on the topic to help me make a better educated decision. I wish I knew what I do now about stringer and transom rot before bought the boat!!

 

[CrownlineRider92]

Here is a picture of the boat. She definitely does not show all the problems that are hidden deep inside!

 

[e5earley]

Currently in a similar situation as far as condition on my boat. I've worked the past couple years to correct all the mechanical issues with the engine and outdrive. I knew the boat had been neglected so there was no surprises for me. Part of my problems was self induced. The boat had sat next to my garage uncovered since last summer. No telling how may hundreds of gallons of water got dumped into the boat off the garage roof. My fault, but other priorities kept it out of site and out of mind. Decided last week to do a check under one of the seats and confirmed what I already knew in my mind. Rotten floor, stringer grid, probably transom.

I decided to delay splash day until I was satisfied that the boat was safe. Which means full tear out, inspection, and rebuild. I too have no experience with fiberglass construction but after looking at the quality of some of the layups from the factory I probably couldn't do much worse. I could have just got it running and eased out on the lake and had fun this season. But I equated it to using an old wooden ladder with sketchy rungs to climb on my roof. I could be easy and would probably make it up and down, but I wouldn't let my wife and kids climb it. So, I got the saw out and made a few cuts. Now it's too late to go back, can't put in on the water, can't sell the boat with it tore apart. Decision made, have to rebuild it.

Good luck with yours. If you decide to tackle it yourself, look for an Airgas store close to you. They have a box of hooded suits that are made with a thin breathable material. I think they sell them for around $30 for 25 suits. Much cooler than trying to work in a Tyvek suit.

 

[Rick Stephens]

As you have already heard, everyone here will sympathize with you. Your problem is one most of us have suffered in our boating histories. When I did mine, it was self inflicted as I knew just what had to be done, and frankly, I had a blast doing the work. Most of the time we try our hardest to deny the degree of rot until we get through the 5 stages, or however many, of grief and accept the reality. The reality is, if you will enjoy working on your boat and making it better'n new, then go to it. It's not on the lake with the family, but it is rewarding. If the reality is you won't enjoy it, and you need to get on the lake, skip it and sell this one, buy another and go boating.

 

[Scott Danforth]

Most of the time we try our hardest to deny the degree of rot until we get through the 5 stages, or however many, of grief and accept the reality.

First stage is denial, followed by argumentation, followed by realization, then acceptance, and asking for help........then we get to the tools of destruction,