Clean out hatch rebuild - wood core replacement

[71BeaterBoat]

I'm the new owner of a 2007 AR230 that has needed a little bit of work to get it water ready for the next season. The first major project I tackled was replacing the wood inside of the deck hatch on the swimstep over the clean out ports. When I inspected the boat before delivery I noticed that the starboard side of the hatch was solid, but the port side was incredibly spongy and had a lot of give on it.

Once I got the boat home I started out by removing the hatch from the boat. After I took the hatch apart I realized the damage was a lot worse than I had expected. The hatch is basically comprised of 3 parts: the tray that is the top of the hatch that you walk on, a wood inner core, and a fiberglass bottom that is meant to seal the bottom to the top and make it waterproof. Unfortunately a crack in the hatch and no sealing inside of the holes for the latches allowed water to penetrate into and rot out the wood core. The wood was entirely missing on half of the hatch. Because of the rotten wood, I had to replace the core of the hatch and rebuild it. The part is discontinued by Yamaha and so unless you can find a used one or from a salvage boat, rebuilding is going to be our only option.

I'm confident that this hatch is waterproof and will not rot like it did previously. I believe that the marine plywood added substantial weight to the hatch, but it's hard for me to compare because 1/2 of the wood was missing from the hatch when I took it off the boat. The hatch appeared to have been built with end-grain balsa wood core from the factory, I don't know if that would be a good replacement core or not due to the rotting that I saw.

Here are the products I used:

1. 1/2" Marine Grade Plywood (No local lumber yard carried 3/8" which is what the hatch actually needed)
2. West System 105-B and 205-B epoxy resin system with metering pumps (I ended up using about 75% of the gallon)
3. acetone
4. fiberglass mat
5. 2x3 wood boards, 8' and 4'

Here are the steps that I used to complete the repair. To begin with, I'm not a professional in this area and this is most likely not the best way to accomplish this. However, it worked for me.

1. Remove the hatch from the boat
2. Remove the latches and support for the gas piston.
3. With the hatch supported, use a small grinder or cut-off wheel to cut along the inner border separating the top of the latch (what I called the "tray") and the bottom fiberglass layer.
4. Once the fiberglass bottom and top layers are cut apart where they intersect, I used a long screwdriver to pry the bottom fiberglass layer from the wood. (This caused some damage to the fiberglass and at least 1 layer of mat was removed in some areas where it was still bonded to the wood.)
5. Using a metal scraper I was able to remove the rest of the wood from the tray.
6. I then sanded the remaining wood until it was level, I wasn't concerned about removing all of the wood to fiberglass. If it was still bonded to the fiberglass I didn't want to damage anymore of that structure than I needed to.
7. Use acetone to clean them fully.
8. I used the bottom piece of fiberglass as a template to measure and cut the marine plywood.
9. Use wax paper on the outside of the hatch fiberglass pieces to cover the holes where the latches go through and secure it using painters tape. Lay the tape as the edges of the hole so that it creates a solid seal around the hole. The less resin intrusion onto the outer layer when you pour it the better.
10. 1 layer of resin on the top tray
11. 1 layer of resin on the bottom fiberglass
12. 2- 3 layers of resin on the marine plywood to fully seal it, making sure that there were no dry spots after the second layer, and using the 3rd to create a smooth surface.
13. 2-3 layers of resin on the exposed edges of the plywood to fully seal it.
14. Fiberglass mat and resin added to the areas of the fiberglass top tray and bottom piece where fiberglass was removed during the deconstruction of the hatch.
15. Resin layer on top of the mat/resin layer to build it up.
16. Sanded the top and bottom fiberglass structures until smooth, making sure not to sand through to the mat.
17. Test fit of the sealed plywood into the bottom tray and sand any points of conflict due to the added resin thickness.
18. 1 heavy layer of resin inside of the tray, then I laid the plywood into the tray.
19. using (2) 2x3 boards along the length of the plywood on the edges and one perpendicular in the middle clamp the plywood down into the tray with even pressure.
20. Once the resin in step 19 is fully cured, fill the outside border between the plywood and the tray with resin until it is full. This may take multiple batches and applications of resin. Once this resin is cured, the tray and plywood core should be 1 solid piece without any gaps or holes.
21. Heavy layer of resin over the plywood and then position the bottom fiberglass piece in place and repeat the 2x3 supports and clamping that was used in step 19.
22. Layer of resin around the outside of the bottom fiberglass to bridge the plywood to the fiberglass smoothly.
23. Sand the bottom layer to tray lip smooth
24. Cut 2 1/2" circular hole for the latches.
25. acetone to clean holes for latches
26. 1-2 layers of resin inside of the holes for the latches to make them waterproof.
27. Sand the holes smooth without sanding through resin and test fit latches.
28. Paint bottom of hatch as needed.

 

[Julian]

Excellent job and amazing write up!

Did you replace the latches or were the old ones functional? Since you couldn't find 3/8 board is the hatch thicker and is it noticeable?

How about a final pic back on the boat?

 

[Bruce]

Amazing work. Thank you for sharing!

 

[71BeaterBoat]

Excellent job and amazing write up!

Did you replace the latches or were the old ones functional? Since you couldn't find 3/8 board is the hatch thicker and is it noticeable?

How about a final pic back on the boat?

I replaced the latches with new because the old ones were corroded but functional. The hatch is thicker and it required me to fabricate spacers to go under the hinges to make it level. Once I get back to my boat on Monday I'll take pictures of it on the boat. It's only noticeably thicker if you're looking for it. I know that it's thicker, but I doubt anyone else would ever notice it.

Due to the increased thickness I also had to adjust the height of the engine kill switches inside of the hatch. That was more of an annoyance than anything since it requires taking off the center cover to get into the bilge area underneath it to adjust the height of the nuts on the kill switches.

For anyone else attempting this project, I would recommend sourcing the 3/8" plywood instead of the 1/2". It would have eliminated a few of the extra steps I had to do.

 

[buckbuck]

Nice work. I had to do the same with my fuel hatch last year. I can appreciate all the work you had to do.

 

[71BeaterBoat]

Nice work. I had to do the same with my fuel hatch last year. I can appreciate all the work you had to do.

Was there anything you did differently that made the replacement go smoothly?

 

[buckbuck]

Your procedure was very thorough. I don't think I could recommend anything different. I sealed the bottom of mine with resin and fiberglass instead of paint only because I needed addition support.
Welcome to the forum and thanks for contributing. We are here to help each other keep our boats in top shape.

 

[71BeaterBoat]

Here is the complete hatch on the boat. Don’t mind the hydroturf, it’s all being pulled up and replaced with hydro deck.

 

[71BeaterBoat]

edited: Thank you everyone for the support. I've gotten the information that I needed.

 

[dgfreeze]

There's a liability concern with publicly sharing copies of the service manual, and moderators particularly need to tread carefully. You might have better luck going to the model specific forum, and asking where one "might be able to acquire" a digital copy of the service manual. Good luck, if someone can help you, they will!

Also, good job on the repairs, hopefully all goes well!

 

[71BeaterBoat]

Thank you @dgfreeze, my apologies to the mods.

 

[Scottintexas]

This was my rotted hatch fixed but i would suggest your method

https://jetboaters.net/threads/clean-out-hatch-is-rotting-fixed.1227/

 

[rayski]

I'm the new owner of a 2007 AR230 that has needed a little bit of work to get it water ready for the next season. The first major project I tackled was replacing the wood inside of the deck hatch on the swimstep over the clean out ports. When I inspected the boat before delivery I noticed that the starboard side of the hatch was solid, but the port side was incredibly spongy and had a lot of give on it.

Once I got the boat home I started out by removing the hatch from the boat. After I took the hatch apart I realized the damage was a lot worse than I had expected. The hatch is basically comprised of 3 parts: the tray that is the top of the hatch that you walk on, a wood inner core, and a fiberglass bottom that is meant to seal the bottom to the top and make it waterproof. Unfortunately a crack in the hatch and no sealing inside of the holes for the latches allowed water to penetrate into and rot out the wood core. The wood was entirely missing on half of the hatch. Because of the rotten wood, I had to replace the core of the hatch and rebuild it. The part is discontinued by Yamaha and so unless you can find a used one or from a salvage boat, rebuilding is going to be our only option.

I'm confident that this hatch is waterproof and will not rot like it did previously. I believe that the marine plywood added substantial weight to the hatch, but it's hard for me to compare because 1/2 of the wood was missing from the hatch when I took it off the boat. The hatch appeared to have been built with end-grain balsa wood core from the factory, I don't know if that would be a good replacement core or not due to the rotting that I saw.

Here are the products I used:

1. 1/2" Marine Grade Plywood (No local lumber yard carried 3/8" which is what the hatch actually needed)
2. West System 105-B and 205-B epoxy resin system with metering pumps (I ended up using about 75% of the gallon)
3. acetone
4. fiberglass mat
5. 2x3 wood boards, 8' and 4'

Here are the steps that I used to complete the repair. To begin with, I'm not a professional in this area and this is most likely not the best way to accomplish this. However, it worked for me.

1. Remove the hatch from the boat
2. Remove the latches and support for the gas piston.
3. With the hatch supported, use a small grinder or cut-off wheel to cut along the inner border separating the top of the latch (what I called the "tray") and the bottom fiberglass layer.
4. Once the fiberglass bottom and top layers are cut apart where they intersect, I used a long screwdriver to pry the bottom fiberglass layer from the wood. (This caused some damage to the fiberglass and at least 1 layer of mat was removed in some areas where it was still bonded to the wood.)
5. Using a metal scraper I was able to remove the rest of the wood from the tray.
6. I then sanded the remaining wood until it was level, I wasn't concerned about removing all of the wood to fiberglass. If it was still bonded to the fiberglass I didn't want to damage anymore of that structure than I needed to.
7. Use acetone to clean them fully.
8. I used the bottom piece of fiberglass as a template to measure and cut the marine plywood.
9. Use wax paper on the outside of the hatch fiberglass pieces to cover the holes where the latches go through and secure it using painters tape. Lay the tape as the edges of the hole so that it creates a solid seal around the hole. The less resin intrusion onto the outer layer when you pour it the better.
10. 1 layer of resin on the top tray
11. 1 layer of resin on the bottom fiberglass
12. 2- 3 layers of resin on the marine plywood to fully seal it, making sure that there were no dry spots after the second layer, and using the 3rd to create a smooth surface.
13. 2-3 layers of resin on the exposed edges of the plywood to fully seal it.
14. Fiberglass mat and resin added to the areas of the fiberglass top tray and bottom piece where fiberglass was removed during the deconstruction of the hatch.
15. Resin layer on top of the mat/resin layer to build it up.
16. Sanded the top and bottom fiberglass structures until smooth, making sure not to sand through to the mat.
17. Test fit of the sealed plywood into the bottom tray and sand any points of conflict due to the added resin thickness.
18. 1 heavy layer of resin inside of the tray, then I laid the plywood into the tray.
19. using (2) 2x3 boards along the length of the plywood on the edges and one perpendicular in the middle clamp the plywood down into the tray with even pressure.
20. Once the resin in step 19 is fully cured, fill the outside border between the plywood and the tray with resin until it is full. This may take multiple batches and applications of resin. Once this resin is cured, the tray and plywood core should be 1 solid piece without any gaps or holes.
21. Heavy layer of resin over the plywood and then position the bottom fiberglass piece in place and repeat the 2x3 supports and clamping that was used in step 19.
22. Layer of resin around the outside of the bottom fiberglass to bridge the plywood to the fiberglass smoothly.
23. Sand the bottom layer to tray lip smooth
24. Cut 2 1/2" circular hole for the latches.
25. acetone to clean holes for latches
26. 1-2 layers of resin inside of the holes for the latches to make them waterproof.
27. Sand the holes smooth without sanding through resin and test fit latches.
28. Paint bottom of hatch as needed.

Very nice work!

Does anyone know if Yamaha still uses wood in these hatches? If not, what year did they shift to all composite materials?

 

[NortherMIBoater]

Excellent work. I noticed the same softness around the corners this weekend taking off the old hydro turf. To be honest I'm nervous about cutting into a part that can't be replaced if I screw it up.

I know Yamaha discontinued this part number but does anyone know if a different part number would fit? Say from a newer model 230?

 

[Scottintexas]

you're cutting the bottom side which is junk/not finished anyways,

it's worse if your hatch cracks on the top side, It may be daunting if you've never done it before but it is a pretty simple process and if you're not good at the finish, it's on the bottom side and nobody sees it anyways,

if I had to do it again (I'll probably end up having to do my fuel hatch) I'd do it per his instructions above,

if you're not going to do it I would suggest taking it off and going to a fiberglass shop for them to repair,


.

 

[Scottintexas]

Excellent work. I noticed the same softness around the corners this weekend taking off the old hydro turf. To be honest I'm nervous about cutting into a part that can't be replaced if I screw it up.

I know Yamaha discontinued this part number but does anyone know if a different part number would fit? Say from a newer model 230?

and glad to have you on board @NortherMIBoater

is your scupper replaced yet ? be sure to check out the link in my signature below for "known issues" and fixes for your model boat,



.

 

[captainhook]

Thanks for posting this, I am about to tackle this myself. This has been an issue on my ski locker for a couple of years and I was planning to use Git Rot or something similar as other members have done, but I took my latch off and it's the consistency of slime inside around the hole so I might as well just do it right (and would probably wind up using $100+ of Git Rot anyways...). Unfortunately the only marine plywood I could find was also 1/2" and only available in 4'x8' sheets for a whopping $100. I considered a sheet of PVC as well, but that was $140 (also only available in 4'x8') and I had concerns that it would flex too much and crack the fiberglass on top and bottom. I initially wasn't going to buy it and go to another idea but I figured there's a 99% chance my cleanout hatch will do the same thing so I'll just keep the sheet in the garage up against the wall, provided I don't decide to go all out and just preemptively fix that now too.

 

[Johnq36]

Your procedure was very thorough. I don't think I could recommend anything different. I sealed the bottom of mine with resin and fiberglass instead of paint only because I needed addition support.
Welcome to the forum and thanks for contributing. We are here to help each other keep our boats in top shape.View attachment 140308

I am currently working on this anytips you might have

 

[captainhook]

So I recently did this, and if I had it to do over again, I would've tried the GitRot injection method. Why? Because it took me a lot longer than I expected and even though I thought mine was rotten in a significant amount of the hatch, it was only like maybe 1/5th of it. So I ended up scraping out a lot of good wood which was a huge pain in the ass. I started with a rubber mallet and a chisel and eventually bought an oscillating tool which made short work of it, but some of the top was damaged and I'll need to fix it. In addition, the only marine plywood I could find was 1/2" and only sold in 4x8 sheets... for ONE HUNDRED DOLLARS. I wound up using some fiberboard I had left over, but that too was 1/2" and my hatch is now too high. Which isn't a big deal, except now I need to shim the hinges.

I would try the GitRot method first, if my cleanout hatch does this, I'll be trying that first.

 

[Johnq36]

Loos like we Yamaha guys are having a lot of fun doing this!! Smh
I might just lay-in my plywood and discard my old cap( the bottom layer of fiberglass) and just make the new glass tight as can be

I really wanted to just fill it with resin then drill out the holes and avoid wood all together.