Transom modification options

[jbrinch88]

I have a 1988 24 offshore with the standard notched transom. Sold my motor and repowering with a 300 yamaha but im going to rebuild the transom first and possibly change the layout. Looking for pros and cons to each option.

- Keep current transom height (25") but close in the sides about 6-8"s

- Raise transom to 30"s and also close in the sides

- close transom in and run a bracket.

Looking to take the boat further offshore once its repowered trying to decide how to layout the transom to take the least amount of water over the stern.

Thanks

 

[Fishtales]

Hard to envision if you get any additional cockpit space if you go with the bracket. I think I'd pick the one that is the easiest to execute and cost the least. Your restoring a 30 year old hull. Probably want to do it right but manage cost at this point (that would be my highest priority factors if in your position). If you have two or more options that are about the same in effort and cost, then really up to you.

 

[suzukidave]

what he said

 

[jbrinch88]

Cost is definitely a concern since I’ll be purchasing a new motor on the spring. Ive considered going with coosa and I know that’s probably the right way to do it, but I don’t plan on keeping this boat for 30 years.

Will probably go with a more affordable high quality marine ply.

I’ve always loved closed transom hull layouts with integrated livewells etc but I don’t feel this hull is worth all that extra cost and effort. I just want to make it reliable and safer offshore with taking water over the stern.

Closing in the 2 sides more would cut down some water significantly and raising the transom height would be even better, however would raising the transom height prevent the perks of having a notched transom from working properly ( bailing water out the back quickly when taking water over the bow)?

 

[gw204]

Cost is definitely a concern since I’ll be purchasing a new motor on the spring. Ive considered going with coosa and I know that’s probably the right way to do it, but I don’t plan on keeping this boat for 30 years.

Will probably go with a more affordable high quality marine ply.

I’ve always loved closed transom hull layouts with integrated livewells etc but I don’t feel this hull is worth all that extra cost and effort. I just want to make it reliable and safer offshore with taking water over the stern.

Closing in the 2 sides more would cut down some water significantly and raising the transom height would be even better, however would raising the transom height prevent the perks of having a notched transom from working properly ( bailing water out the back quickly when taking water over the bow)?

From what I remember of the 24 Offshore, the transom cutout is EXTREMELY low. I would absolutely tighten up the sides, go 30" and add some sort of substantial removable bulkhead. Should have little effect on the ability of the hull to shed water and you'll be much safer in the big pond.

 

[suzukidave]

Cost is definitely a concern since I’ll be purchasing a new motor on the spring. Ive considered going with coosa and I know that’s probably the right way to do it, but I don’t plan on keeping this boat for 30 years.

Will probably go with a more affordable high quality marine ply.

I’ve always loved closed transom hull layouts with integrated livewells etc but I don’t feel this hull is worth all that extra cost and effort. I just want to make it reliable and safer offshore with taking water over the stern.

Closing in the 2 sides more would cut down some water significantly and raising the transom height would be even better, however would raising the transom height prevent the perks of having a notched transom from working properly ( bailing water out the back quickly when taking water over the bow)?

a bracket hull is still seaworthy and is much slower to drain water than an 80s era notched transom with the wide notch and the wide open splashwell and low transom. even a modern notched transom will drain more slowly.

i think if you end up with the same drainage capacity of a more modern equivalent boat you will be ok.

 

[UCPA111]

I enclosed my seafarer. 1984 model. Added a custom floatation bracket from Custom Marine Welding and hung a brand new Mercury Verado 300 with Vesselview and power steering. I am tickled. Boat has a TON of cockpit space...I gained a bunch by enclosing the transom. And, much more secure. 28-30 mph cruise at 2.76 mpg. Top end is 48 mph all day long (with hard top, 3/5 fuel, 4 people) and I've hit 50 when a little lighter.

You can see my videos of what I did on my youtube page.
https://www.youtube.com/channel/UCATvLuuBWqIPmRX0gH9FiMQ

I went with Coosa board, 1708 mat fabric, cut strand mat, and West System 105 epoxy. It's stout! Yes, you pay a bit for Coosa (I laminated two sheets of 1" together), but I loved working with it (easy to shape, strong, and light!).

 

[jbrinch88]

I enclosed my seafarer. 1984 model. Added a custom floatation bracket from Custom Marine Welding and hung a brand new Mercury Verado 300 with Vesselview and power steering. I am tickled. Boat has a TON of cockpit space...I gained a bunch by enclosing the transom. And, much more secure. 28-30 mph cruise at 2.76 mpg. Top end is 48 mph all day long (with hard top, 3/5 fuel, 4 people) and I've hit 50 when a little lighter.

You can see my videos of what I did on my youtube page.
https://www.youtube.com/channel/UCATvLuuBWqIPmRX0gH9FiMQ

I went with Coosa board, 1708 mat fabric, cut strand mat, and West System 105 epoxy. It's stout! Yes, you pay a bit for Coosa (I laminated two sheets of 1" together), but I loved working with it (easy to shape, strong, and light!).

When you cut back your stringers back were they wet or rotted? Mine appear to be pretty wet i drilled some small holes into the tops and sides of them and im pulling out some wet core. Some spots worse then other wont know until i asctuallynstart cutting.

If yours were wet how did you end up bonding the new ones to the old ones? I might end up replacing whats necessary and then sistering them with a new set of stringers and tabbing them into the floor and transom as well. Or if theyre really bad ill just cut them back to the bulkhead that isolates the fuel tank compartment and run new ones.

 

[UCPA111]

When you cut back your stringers back were they wet or rotted? Mine appear to be pretty wet i drilled some small holes into the tops and sides of them and im pulling out some wet core. Some spots worse then other wont know until i asctuallynstart cutting.

If yours were wet how did you end up bonding the new ones to the old ones? I might end up replacing whats necessary and then sistering them with a new set of stringers and tabbing them into the floor and transom as well. Or if theyre really bad ill just cut them back to the bulkhead that isolates the fuel tank compartment and run new ones.

On the port side, I saw some softness where they had drilled some holes/had mounted items. I cut it out. I then refilled with epoxy. When I cut out the transom I had to cut the stringers back as well to gain access. So, those pieces I cut out - I cleaned them up. Filled them in with epoxy where soft. When I reinstalled them I made epoxy puddy to bond all together, then I wrapped in fiberglass and resin to join back to original stringer. And then (yeah, I know), I laminated a piece of coosa alongside with puddy (to bridge the join and connect back to transom)and wrapped that with 1708. It's stout. I wanted a lot of strength to reconnect along the transom. I knew I was going to have the bracket and the motor 28" off the back. It is rock solid.
So, yes, I sistered. Wrapped. Tabbed.

 

[jbrinch88]

I will probably end up doing the same. Rather over do it then have it not be strong enough.

How did you go about properly supporting the hull when you starting cutting apart? Boats currently on a roller trailer, I was going to put some blocks in the center most aft portion of the boat and two boatstands in each side of the hull as well

 

[UCPA111]

I had the boat on the trailer - bunk trailer. We cut away the gunnel a couple feet forward of the transom on each side. Pulled that off and kept. Then, I scribed a line down each side and across the deck and up the other side. Used a vibratory (ultrasonic) rockwell tool with sharp blade. Made a nice, straight cut. Had to split along centerline. Pulled out the two pieces. Then, removed inner fiberglass and wood. Maintained exterior hull structure. If you checkout my videos, you can see. There was no reason to have additional support. Everything stayed put.

The Rockwell vibratory tool made the work soooo much easier. I used that extensively. I also used a 4" angle grinder with 40 and 60 grit flap disk sanding heads. It ate it up (made a crapload of dust though).

The deck of the seafarer had some steps in the back as it went to the transom. I ended up filling those in to make a nice, flat deck. I created "scupper wells" in each corner. They work fantastic. I installed new scupper covers (maintained 2 holes per side close together that are thru the transom). http://www.replacementboatparts.com/rectangularstainlessscupper.aspx

 

[UCPA111]

I imagine you could go single 350 with your boat. The Verado 350 is the same motor I have but with enhancements to supercharging system. I am tickled with the Verado. At the launch, I get to hear Yamaha, Suzuki and others firing up. I fire up, and people have commented they cannot believe my 300 is quieter than their 200, 250, etc. 4 strokes. I had a lady comment once and it made me laugh. She said, "I cannot get over how quiet that motor is." I said, well, you have a 4 stroke motor as well. She said, "it's not THAT quiet." Funny. I told her is should be quiet for what I paid. LOL!
The midline punch of the supercharger is amazing.
I can troll on Lake Erie with the motor. 2 mph. The VesselView lets me control RPM in 10 rpm increments through the screen in troll mode. It's fantastic. You can't even tell the motor is running except for the pee stream noise.

Nothing wrong with Yamaha...great engines....I wanted to give Mercury a try to do something different. Power steering, Vesselview, and Inline 6. Silky smooth. If I hadn't installed the Verado, I would have gone with Yamaha 300.

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