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Discussion Starter · #1 ·
So I was preparing to pull my engine today to start the rebuild. (I know wrong time of year to do this!!) When I pulled the through hull exhaust tips off I discovered that the transom is rotted pretty bad. When I pushed on the outside I can feel where it is spongy... So my motor project has now turned into needing to replace the wood in the transom. I have searched the forum and found some info on this. Does everyone still agree that using a circular saw with the blade depth set at the wood thickness is the way to go about cutting out the inner transom? What should I use to replace the rotten wood Marine grade plywood or something else?? I will try to get in touch with one of the local boat builders to see if he can install the new transom. I think that is way out of my novice fiberglass league. Anything else I should be looking for or should do???
 

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can't use marine plywood, glass won't stick to it. Definitely get help on this one, its not a job for a novice to sit and figure it out. You need to get the layup schedule right and keep the outside skin straight so you end up with a flat transom. You are going to need the templates to cut the holes for the drives also.

Circular saw works, once you start cutting pieces out it will start to just fall apart if the whole thing is wet.

ahh shiit, I meant treated plywood.
 

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I would REALLY have to be in LOVE with a boat to tackle that!!

My fix would probably consist of an orange and black sign, then posting some classified ads...then an Ebay auction as a final result.

But if the rest is good and worth savin', good luck with the project!
 

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Its not gonna be bad if youre already pulling the engine out any way. I would use marine grade plywood, and if you seal it around all the cutouts, it will last forever. Lots of info onlline anbout this, and if you use West sytems epoxy, they have a very informative booklet that will steer you along. A transom rebuild is not that big of a deal, and I think it is the perfect job for a novice to get started. Stringers, floors etc are harder. You can do it all in a day, while your waiting for parts for the engine! And now you will know that the transom is good.
 

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tmthunder said:
I thought that glass would stick to Marine plywood but not to pressure treated wood?????

I agree, I replaced my transom on the Wellcraft and used 2 sheets of 3/4'' marine ply. I also looked into using pressure treated lumber but it would seem that pressure treated lumber releases It's treated chemical slowly and would eventually not adhere to fiberglass resin.
The first step when buying materials is to know what kind of resin they used to construct your boat.

Polyester resin WOULD NOT adhere to epoxy resin

Epoxy resin would adhere to Polyester

This is how I did my transom, removed the engine and cut out the inner skin removed the rotted wood and sanded off the rotted stuck on wood/glue/resin from the inside of the outer skin. You Must get is nice and smooth,then clean with Acetone.
Use some construction paper and cut out a template of the outer skin where the marine ply has to go.
Cut your two pieces of ply the same then use a two part epoxy glue and stick them together,use some clamps to really squeeze them together. seal the outer edges of the ply while you have the glue out.
Don't have a clue what thickness your transom is but measure the thickness to determine the thickness of ply to buy.
Wipe the inside of the outer skin again with some acetone, wait a few minuets , then glue your glued double sheets of marine ply to the inside of the outer skin. Use some planks of wood to wedge it tight against the outer skin.
I used a plank of 2x4 across the ''outside'' of the skin and drilled it into the marine ply where the drive cutout is,this would help pull the ply to the skin.

You would need 2 layers of fiberglass over the ply,again you have to know the thickness of your existing transom. Your marine supplier would determine what oz glass to buy.
I may have some pix of my job, I'll post them up later for you.
Steve
 

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we recored my brothers whole boat last summer, was no big deal at all.....its not fun work, but its not that hard if you take your time and do it right.

I would core the transom with this.



These panels come in 4'x8' sheets. They are 50% lighter and 20% stronger than marine grade plywood. It is also virtually impregnable by water intrusion, unlike plywood. We use these panels for full length stringers, transoms, transom knees for outboards, bulkheads, flooring, V-bunk, and cabin seating.

http://www.cyber-marine.com/product_info.php/manufacturers_id/207/products_id/2942

My boat is completely cored with that stuff, we also used it for my brothers boat last summer, it is easy to work with, super light, strong, etc. I wouldn't shy away from a transom repair, but I would order the right stuff and do it right.
 

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Discussion Starter · #8 ·
Thanks for the help guys! I went ahead today and stripped everything off/out of the transom. I am bringing it to a guy I know who builds boats for a living to have him install the new wood and glass. I will post some pics of the finished project in a week when I get the boat back...
 

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When I removed the 3" tips from my transom, I noticed the wood was in pretty bad shape.

In 1997 when I blew my outdrive due to improper service from a dealer in Jax FL :mad: it broke the seal around the transom and the lower unit... while getting a new drive, a boat shop in middleburg FL told me the transom was all rotted and need to be replaced, so I OK'd the $2500 repair... I really green back then and didn't question the work, I didn't know what to look for anway.

Well, now it appears this a-hole simply put new glass over the old wood, so I have the fiberglass hull, then 2" of bad wood, and then another layer inside the engine compartment. :mad:

I drilled new 4" holes for new exhaust, and before putting the tips in, crammed alot of silicon in the area between the two layers of fiberglass where some of the old wood had come out... I don't have time to mess with that part of this job right now. The outside hull is pretty solid and thick, if it sinks it sinks. :unhappy1:
 

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WOW
Looks like nice work
Bet ya had some time just into fab-in all your clamps, huh?
If you're gunna do it...And it looks like you did it right!
NICE
 

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Discussion Starter · #15 ·
Wow that looks great!!! You just gave me an idea also. I am adding a different exhaust to my 502 so I will not beable to mount my shift bracket in the orginal location but after seeing your pictures it just clicked that it can mount anywhere . Thanks!!! What did you put in for an engine and drive combo?
 

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Well, my transom is as bad as I was hoping it was not... so I am going to have to have it replaced.

I don't have the space, tools or time to tackle anything like this, can anyone recommend someone in the midwest area who is reputable (Kansas, OK TX, AR, MO)?

The boat probably isn't worth this, but I have already sunk way more into this project than I should have. :(
 

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Discussion Starter · #17 ·
Sorry to hear that H8tank. I picked my boat up last Monday. THe guy did a great job but Maine is a little far away for you. I will get some pics up later on.
 

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Discussion Starter · #20 ·
Total was 1500 out the door. He told me 1000 but it took him a lot longer than he thought because the lower part of the transom was not rotted and required a lot of time to chisel out.
 
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