Broken transom

[sti1471]

Went outboating today and once we were out there the wind picked up and start drifting my boat towards the weeds near shore. The engine of course would not stay running in gear to get us out of there. So I turned on the motor and presed in the neutral button and started to rev the motor to get it to warm up. (was turned off fighing for a a while) While I was revving it at around 2000 RPM the dang thing kicked into gear and jerked the boat and then shut off. After we finally got it going we noticed we were taking on more water than the bilge pump could empty.

Once on the trailer I noticed the engine mount had broke through the transom of the boat.

It is a 16ft fiberglass boat with an 80HP motor.

Pictures show the damage... HOw much will this be to fix, or is it even able to be fixed? Do they make kits to fix this like a metal plate to place on the outside of the boat once the fiberglass is repaired.

Thanks all.

 

[CharlieB]

Re: Broken transom

You may find the wood in the transom is going soft, this was about to happen sooner or later, more likely sooner.

Google 'Transom Repair' you will find a number of pages and products detailing how to gouge out the soft wood within the transom, and how to go about re-filling the void.

You can take the whole transom off, literally rebuilding the azz end of the boat, or gouge out the wood from between the inner and outer layers of 'glass, and fill the void with an expoxy-type resin. Both methods work, depends on how you want to do it and the HP rating you expect to handle after repairs.

 

[j_martin]

Re: Broken transom

Yep. There's nothing left of the core wood in your transom. Maybe stringers and floor boards are rotten too.

Most boats can be split, repaired to like new, and put back together. Whether it's worth the work is up to you.

This thread doesn't belong here. No doubt the mods will move it soon.

 

[hotrod53]

Re: Broken transom

Yep, looks like you had hidden rot and like previously said, it was going to happen anyway. I just replaced my transom and my floor in my aluminum boat, but your proceedure will be different. Marine plywood is about $75/sheet for 3/4" and it takes 2 layers, marine epoxy is available on Ebay for a reasonable price, but I have no idea on the fibreglass part. If you're stringers are bad, that looks like a lot of work, I'm liking my aluminum boat about now. I was down to the hull with mine, it takes a lot of time and a lot of work to rebuild one. Might be one of those things that its only worth it if you do it yourself, paying someone may not out weigh replacing it.

 

[sti1471]

Re: Broken transom

OK,

So lets say the wood is not rotted out, can I do the following?

Can I remove the engine and cut out a 6x6" square at each hole, fiberglass the inside of the boat, and then fill the 6x6 squares with epoxy and then fiberglass the outside? If the wood is not rotted, I don't want to replace the entire transom. Or can I fill the 6x6 holes with epoxy and then put a 6x6" stainless steel plate on the outside of the transom with something like 5220 on it to seal it, then mount the engine through the 6x6 metal plates, and through the new epoxy I put in?

 

[sti1471]

repair hole in transom

repair hole in transom

I got a 1988 16ft fiberglass boat. I went out in it yesterday and when i was throttling the engine in neutral to warm the motor up, for some reason it kicked into gear and jerked the boat forward real quick before dying.

Once we got it on the trailer, I noticed the engine plate had broke through the transom. The inside of the boat has a crack in the fiberglass, but nothing big. the outside has a hole on each mounting rail.

I have heard of seacast, but I want to also entertain the idea that the wood is not rotted, and it was the 80 HP motor kicking into gear too fast that just broke the healthy wood.

Can I remove the engine and cut the holes bigger to 6x6" square at each hole, fiberglass the cracks inside the boat, and then fill the 6x6 squares with epoxy or seacast and then fiberglass the outside? If the wood is not rotted, I don't want to replace the entire transom.

Or can I fill the 6x6 holes with epoxy and then put a 6x6" stainless steel plate on the outside of the transom with something like 5220 on it to seal it, then mount the engine through the 6x6 metal plates, and through the new epoxy I put in?

 

[j_martin]

Re: Broken transom

I hate to say this, but that transom is really bad. This one manifested as loose upper mounting bolts on a V6 150 hp engine.

You can bet on all the wood in the transom being totally rotten and soaked with water. You may also have wet flotation foam in the floor, and if it has wooden stringers, they are probably also bad. In short, your ship is sinking, literally.

The only way to tell is to take the top off the transom and look. Repair involves removing at least some of the cap so you can cut away the inside fiberglass, replace the wood, and relay that part of the boat. You also have a major tapered fiberglass repair to the outside of the transom in store, as it has already been punctured badly. Any patch as you suggest will put you and your riders at grave risk, especially in rough or cold water.

 

[Yacht Dr.]

Re: repair hole in transom

Re: repair hole in transom

Sorry mate .. full trans job is what I see ..

You might have been lucky that it was only on the start up .. not FOT with a break.

Need more open/wide pics of the boat side and overall please ..

YD.

 

[sti1471]

Re: repair hole in transom

Re: repair hole in transom

So there is a not a way to put marine tex, or they don't make a putty hole filler for something like this?

I know seacast is great stuff to repair this, but when I put in my info it said I needed 15 gallons. For a 16ft boat? The max width of the boat is 48". Seems like a little much material.

 

[jigngrub]

Re: repair hole in transom

Re: repair hole in transom

Your transom is rotten and you cannot just patch the hole, it'll only break again and you may weel lose your engine next time... and this is probably just the tip of the iceberg as far as your rot problem goes, youll see when you start taking stuff apart to fix the transom.

I figured your transom at 48" wide, 24" deep, and 1.5" thick and came up with 8.64 gallons. How deep is your transom at the deepest point?

Seacast will be tricky for you to work with and you should read up on it extensively before attempting to install it.

 

[sti1471]

Re: Broken transom

Would it be easier to just dig out the bad wood, and place it with marine grade plywood?

What are alternatives to the marine grade plywood? I have read on a few boat sites that people will use exterior plywood, and either coat it in epoxy, or a glass cloth shell.

Is there a problem with this method of using normal plywood V.S marine plywood if it is epoxy or class cloth coated?

The boat is an 1988, I figure there is about 2-3 years of life left before I upgrade. Will the regular plywood soaked in epoxy or other marine sealer last 5 years or so?

 

[jigngrub]

Re: Broken transom

Exterior grade plywood (sheathing) will work well enough. You can epoxy it, glass it, or urethane it. Don't use pressure treated plywood from a lumberyard, it has a high moisture content and you coatings won't penetrate or bond.

 

[j_martin]

Re: Broken transom

As I explained, your boat is broken and rotten inside. Fix it right, or replace it, or be very unsafe.

The structural strength of the transom is the wood. The fiberglass is only a laminated cover. The wood is gone. It's broken very badly, and you are fortunate you didn't lose your engine, or worse yet, your life.

As I and others have posted, the structural integrity (read that safety) of your boat is in question and needs to be evaluated and repaired.

 

[j_martin]

Re: Broken transom

Would it be easier to just dig out the bad wood, and place it with marine grade plywood?

What are alternatives to the marine grade plywood? I have read on a few boat sites that people will use exterior plywood, and either coat it in epoxy, or a glass cloth shell.

Is there a problem with this method of using normal plywood V.S marine plywood if it is epoxy or class cloth coated?

The boat is an 1988, I figure there is about 2-3 years of life left before I upgrade. Will the regular plywood soaked in epoxy or other marine sealer last 5 years or so?

1. I've done the arthroscopic transom replacement routine. If I had it to do again I'd pull the cap, and my boat is a bass boat, it takes a lot of cutting to pull a bass boat cap.

2. BCX will work ok if it's good and dry. Marine plywood does not have any voids in the core, and X plywood does. For High performance, use marine. It might be important when you bolt a coupla hunnert ponies to it.

3. I soak plywood I use in Rot Doctor CPES. Then I use epoxy to complete the repair as bonding with poly would be suspect.

4. An '88? Might be best to cut the losses, involve the bank in an upgrade now and send this one to the dump. Depends on condition, emotional value, etc. Be realistic, rotten old boats don't have much value, in fact it's usually measured with a - sign.

hope it helps
John

 

[sti1471]

Re: Broken transom

So if I decided to get a new(er) boat and get rid of this boat, what do you think I can sell my engine for?

It is an 1983 80HP mercury outboard with thunderbolt ignition. Motor works great.

So selling this engine locally, how much can i expect to get for the motor, as this money would go towards a newer boat.

Right now it is in a marine shop getting the damage evaluated.

 

[ezmobee]

Re: Broken transom

$800

 

[sti1471]

Re: Broken transom

OK

So I got word from the marine shop. They tell me that the wood in the transom is not rotted out. They tell me that the engine reving at 3000 RPM and then kicking into gear was too much power with 80HP and broke the wood inside the transom.

They gave me 2 options that will fix this issue.

#1- Gut out the transom and use seacast to build a new transom = $1100.00

#2- clean out the hole, bevel the edges and fill the holes with a marine putty such as marine tex. Then do a fiberglass repair over the marine tex. After the fiberglass repair, cover the transom with a 1/2" thick aluminum plate with and cover the back of the plate with sikaflex291, and bolt the plate to the transom every 8 inches. Then apply Teakdecking caulk around the edges of the plate to seal it from water getting in behind the plate. Seal the crack on the inside of the transom with fiberglass repair. Then bolt the engine to the aluminum plate and through the transom.

They told me that since the boat is a fishing boat, and I plan to maybe upgrade my boat in a couple of years, the 2nd route is that would be best for me.

This is also a good option as my neighbor said he can get an aluminum plate for this at almost no cost.

So by using this option I am basically building a new transom by sealing off the old one, and adding the "transom" to the outside of the boat.

The attachment is what I created based of what the guy drew out how it would work.

Thoughts?

 

[Outback Jack]

Re: Broken transom

I don't believe anyone here is going to go for option b. The transom has already broke , so that being said it is a safety issue, for anyone on board .By you drilling holes every 8 inches to attach a piece of metal is only giving your transom a new spot to break if this happens again. I would either go with seacast or change the whole thing . Safety first.

 

[sti1471]

Re: Broken transom

ok so since the wood is not rotted in the transom, doing a full gut out and repair would be not needed in this case. So since the wood is in good shape, what is another option of repair?

 

[Fzy1]

Re: Broken transom

What it boils down to is Safety and cost vs cost. I had a similar problem, just rot everywhere. my Arrow glass Cougar is part of a land fill now. I could not afford the repairs and I was not going to take it out on the water with out them. Safety must come first!