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Johnp0328

1976 230 slow rebuild begins.

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As title says, I recently received a 76 230 in a trade, Will be working on her slowly but surely as my time is limited for a while. As you can imagine, I have my fair share of questions already. First where is the fuel fill filler originally located? Judging by what I have left on my boat iam assuming this boat had the fuel fill in the center console, The vent still is ran to the side of the hull, but the filler house was only about 2 feet and ran towards what would have been my center console(boat did not arrive with console). I gutted the rear transom today (plan to do a pour transom) and after removing a giant aluminum plate that was holding it all together(not sure why people fix things wrong) I noticed there was 2 drain holes very near the bottom of transom does this have a purpose? Done from the Factory? Here is some pictures of the project today.

C8EADB65-9557-4444-A967-E248110802D2.jpeg

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Should have only been one garboard drain in the transom.  And I agree with ya on the aluminum plates...they really don't add any strength to the overall structure, just covers up the problem for a while.

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4 hours ago, 2-N-TOW said:

Should have only been one garboard drain in the transom.  And I agree with ya on the aluminum plates...they really don't add any strength to the overall structure, just covers up the problem for a while.

Iam I wrong to think that the drain should have a plug? I’ve only owned a few boats and all relied on a bilge pump, so excuse My ignorance.I believe I might be cutting the rear of transom out and doing a Coosa board transom after realizing I couldn’t prep the fiberglass how I would like for the Seacast( although claim to fame is no glass prep I don’t trust it). Any chance you have a picture of original fuel fill? Thanks for any and all tips you can give this newb.

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John,   If you're worried about transom compression, you might want to check out  Carbon Core pourable transom .  I am currently doing a re-core on my R-236 with the motor on a Gil Bracket.   I looked at Seacast and yes it is little lighter because it is a foam product BUT  I went with the Carbon Core  (www. carboncore.com)  BECAUSE  SeaCast compression ratio is only 700 lbs psi, whereas  Carbon Core is  3,895 psi !!   

Just my 2 cents, but with a 200 4 stroke hanging out on the bracket, I want to be able to tighten up those bolts an not have to worry about compressing the core.

 

Don    "The Dr. Ann"    1975'  R-236

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You are correct in that smaller boats sometimes did not have a thru-transom drain.

The drain should have a plug.  This is what I have on my boat:

image.png

https://www.go2marine.com/product/388236F/sea-dog-captive-garboard-drain-plug.html?WT.srch=1&WT.mc_id=gb1&utm_source=googlebase&utm_medium=productfeed&utm_campaign=googleshopping&gclid=Cj0KCQiA6JjgBRDbARIsANfu58GtxsHl6LaXb8-N4GcCLtt4Kb_kb6w1eDBUdB9rtymX5scD4P-bHG0aAhshEALw_wcB

The nice thing about this type is the plug cannot be lost like a typical drain plug.

As for cutting the back layer of glass off to prep the inside for a poured transom, that is not unusual at all.  Removing the outer skin allows for a more thorough cleaning of the internal surfaces.  Just be sure to leave at least a 2" flange around the perimeter when you cut the glass so when re-attaching the skin, you will not have to deal with glassing around the corners where the hull side and transom meet.

Regarding the fuel fill location, trying to find a picture of a 1976 boat is going to be hard.  I would think re-locating the fuel fill to the gunwhale would be a good option, then you would not have to build a flat vertical area into the side of the console for the fuel fill.

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If you are going to cut the outer skin away to prep the interior then using marine ply or coosa and rebuilding in sheets really isnt that hard.  We used marine ply to do ours and its still going strong 15 years later.  

the pour-able transom fixes are a compromise in my opinion.  

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Thank you guys for the tips. Fretz reason I was considering a pour transom was because due to the natural slight bend in the transom,I figured it would be harder to replicate.At this point thou, if iam cutting glass I might as well do it the old way.Believe it or not Seacast specifically states not to cut out the transom for some reason or another. I guess I will be buying some board and epoxy and going to work. 

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Ok John, now you have me scratching my head.  So you are saying the transom has a slight bow in it?  I don't recall Robalo ever building a hull with a curved transom.  I suspect what you are seeing is the effects of a weak transom being run over time and that aluminum plate was not adding any strength to the transom  at all.  As the old transom core dis-integrated, the weight of the  motor caused the transom to bend. 

An easy way to confirm this is check the inner skin of the transom...I bet it is straight.  The inner and outer skins would have been parallel to each other, separated approximately `1 1/2 inches by the 2 layers of 3/4" plywood.  The bend would also cause issues where the motor is bolted to the transom in that unless you had a flat area where it bolted in place, the engine bracket would not lay flush against the outer skin.  I would re-install the skin flat against the core with no bend in it.

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On 12/5/2018 at 8:43 PM, 2-N-TOW said:

Ok John, now you have me scratching my head.  So you are saying the transom has a slight bow in it?  I don't recall Robalo ever building a hull with a curved transom.  I suspect what you are seeing is the effects of a weak transom being run over time and that aluminum plate was not adding any strength to the transom  at all.  As the old transom core dis-integrated, the weight of the  motor caused the transom to bend. 

An easy way to confirm this is check the inner skin of the transom...I bet it is straight.  The inner and outer skins would have been parallel to each other, separated approximately `1 1/2 inches by the 2 layers of 3/4" plywood.  The bend would also cause issues where the motor is bolted to the transom in that unless you had a flat area where it bolted in place, the engine bracket would not lay flush against the outer skin.  I would re-install the skin flat against the core with no bend in it.

Your right no bend, at this point maybe I need a eye test.I had a couple hours today to work on her so I cut out the outer skin. I ordered okume marine grade wood and west systems epoxy last week.Iam glad I went this route because the more I tear into it the more things I find that need repaired correctly. Lots of clean up still needed before I break out the new material. Iam thinking iam going to apply a layer or two of 1708 on the inner skin as it is pretty thin compared to the outer skin. Thoughts of applying new glass on the inner before creating the new transom?

2CD35027-2BE9-4ECB-9A7A-B1E17ECE368D.jpeg

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What is the condition of the transom core beyond the cutout area?  Is that a putty type material that is white on the inner skin, like someone had done a prior repair?

Grind off all that mess on the inside of the inner skin using a 36 grit disc.  You want a clean, rough finish for the new material to grab onto.  Try to not grind into the existing glass much.  Two layers of 1708 should be sufficient to build out the skin back to the original thickness.  The last layer of glass will need to be hit with the grinder prior to installing the core for the same reason the original glass was scuffed...to promote good adhesion.

Once you get to solid transom coring, try to cut the coring at a bevel where the new core and old core will overlap.  Ideally, a 30 degree bevel would be perfect so you have a large area for the joint to spread its load.  If you were to butt the new core against a straight cut, there is a good chance the core could crack over time at the joint.  Even a 45 degree joint would be better than no bevel. 

Use 2 part epoxy or vinylester resin to bond the new core to the old core and to laminate the sheets together.  Vinylester resin has much better bonding strength than polyester resin, but not as strong as epoxy...it is a good compromise between the two.  It does run a little more than polyester, but much less than epoxy.  It also is a more durable resin than poly, and is not that hard to work with.  When you glue up the core, first coat the area to be bonded with the epoxy/resin and let it soak into the wood.  While that is happening, mix up some  more epoxy/resin thickened with cabosil to form a putty consistency.  When bonding the core to the fiberglass, use a notched spreader like what is used for floor adhesive on either the wood or inner skin.  When positioned against the fiberglass, the putty will spread out and fill any irregularities.  Figure on running screws with fender washers through the skin into the coring to pull everything up tight.  Also, if using vynilester, try to keep the resin cool prior to mixing with the hardner to give you a longer set-up time.  The cabosil holds heat in the mixture that is generated during the curing process and it will cause it to set up faster than normal (found this out the hard way years ago!).

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22 hours ago, 2-N-TOW said:

What is the condition of the transom core beyond the cutout area?  Is that a putty type material that is white on the inner skin, like someone had done a prior repair?

Grind off all that mess on the inside of the inner skin using a 36 grit disc.  You want a clean, rough finish for the new material to grab onto.  Try to not grind into the existing glass much.  Two layers of 1708 should be sufficient to build out the skin back to the original thickness.  The last layer of glass will need to be hit with the grinder prior to installing the core for the same reason the original glass was scuffed...to promote good adhesion.

Once you get to solid transom coring, try to cut the coring at a bevel where the new core and old core will overlap.  Ideally, a 30 degree bevel would be perfect so you have a large area for the joint to spread its load.  If you were to butt the new core against a straight cut, there is a good chance the core could crack over time at the joint.  Even a 45 degree joint would be better than no bevel. 

Use 2 part epoxy or vinylester resin to bond the new core to the old core and to laminate the sheets together.  Vinylester resin has much better bonding strength than polyester resin, but not as strong as epoxy...it is a good compromise between the two.  It does run a little more than polyester, but much less than epoxy.  It also is a more durable resin than poly, and is not that hard to work with.  When you glue up the core, first coat the area to be bonded with the epoxy/resin and let it soak into the wood.  While that is happening, mix up some  more epoxy/resin thickened with cabosil to form a putty consistency.  When bonding the core to the fiberglass, use a notched spreader like what is used for floor adhesive on either the wood or inner skin.  When positioned against the fiberglass, the putty will spread out and fill any irregularities.  Figure on running screws with fender washers through the skin into the coring to pull everything up tight.  Also, if using vynilester, try to keep the resin cool prior to mixing with the hardner to give you a longer set-up time.  The cabosil holds heat in the mixture that is generated during the curing process and it will cause it to set up faster than normal (found this out the hard way years ago!).

Wow thank you for that great response! You answered a few questions before I could ask.

The white material I believe is thickened epoxy with some sort of filler? Not exactly sure, all I do know is it is hard as rock as the chisel does not phase it, tomorrow I will start sanding it and hopefully it sands as good as it set up.I will update thread with pictures tomorrow.2-N-tow thank you for all the great info.

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So I presume this will be a dumb question can I hollow this foam out down the middle all the way to the fuel box and install a bilge pump?for that matter can I just hollow all the foam in the rear  of the boat?

25E226DD-A36F-4FA6-9E69-091087E3AEBB.jpeg

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What you have done so far looks good.  In the first picture, is there any fiberglass extending down from what you have sanded on the forward skin to the hull?  Can you post a picture similar to the last picture with the camera inside the outer skin close to the bottom of the hull looking back to the port side?  I want to see if that transom was tabbed into the hull, but something just looks odd in that last picture. 

Also, is that core material behind the outer skin good and solid?  Just wondering as it looks black in the picture.  If it is questionable, now is the time to take the rest of it out all the way to the hull sides.  It can be done without having the cut the outer skin any more.  An electric chain saw with very little bar oil will get the bulk of it out, then finish up with a chisel.  New core can be installed in multiple pieces to get it behind the outer skin.

Don't remove all the foam from the rear of the boat.  It serves multiple purposes: (1) floatation, (2) sound deadening, and (3) provides some structural support to the hull liner.  No problem removing foam along the centerline to facilitate drainage.  Just be aware that if that boat has the in-floor fish box, the thru hull drain is on the center line, too, and you will need to work around that.  If you can get the foam removed all the way to the coffin box, consider installing a drain in the box so any water can get out instead of sitting around the tank.  One thing about doing this, though, is the potential for gas to drain into the bilge if the tank should spring a leak.  Something to think about if you go that route (prior owner installed a drain in my coffin box and I always check the bilge prior to each trip for any gas fumes).

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18 hours ago, 2-N-TOW said:

What you have done so far looks good.  In the first picture, is there any fiberglass extending down from what you have sanded on the forward skin to the hull?  Can you post a picture similar to the last picture with the camera inside the outer skin close to the bottom of the hull looking back to the port side?  I want to see if that transom was tabbed into the hull, but something just looks odd in that last picture. 

Also, is that core material behind the outer skin good and solid?  Just wondering as it looks black in the picture.  If it is questionable, now is the time to take the rest of it out all the way to the hull sides.  It can be done without having the cut the outer skin any more.  An electric chain saw with very little bar oil will get the bulk of it out, then finish up with a chisel.  New core can be installed in multiple pieces to get it behind the outer skin.

Don't remove all the foam from the rear of the boat.  It serves multiple purposes: (1) floatation, (2) sound deadening, and (3) provides some structural support to the hull liner.  No problem removing foam along the centerline to facilitate drainage.  Just be aware that if that boat has the in-floor fish box, the thru hull drain is on the center line, too, and you will need to work around that.  If you can get the foam removed all the way to the coffin box, consider installing a drain in the box so any water can get out instead of sitting around the tank.  One thing about doing this, though, is the potential for gas to drain into the bilge if the tank should spring a leak.  Something to think about if you go that route (prior owner installed a drain in my coffin box and I always check the bilge prior to each trip for any gas fumes).

A little confused about the particular picture your looking for but I have a bunch I will post, After all who doesn’t like pictures? Yes the remaining wood behind the glass is bad as well, I figured I’ve came this far might as we do it completely correct, so that wood will be ripped out and a complete transome will be done.

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Let me try this again.  I was thinking there should be a fiberglass piece extending all the way across the boat; not just at the wet well.  Thought process was the transom was isolated from the rest of the hull below deck.  I went back and reviewed the pictures when I pulled my transom out and did not see any indication of a fiberglass piece/skin that would be on the forward side of the transom core.

Since all work is being done from the outside, once you have fit the wood for the transom core, any area on the front side of the core and the edges will need to be "hot coated" with resin/epoxy to seal out moisture.  Also, prior to sliding the core into place, you will need to mix up some thickened resin/epoxy and run a real big bead along the hull sides and bottom.  When the core is installed, it will bed down in this, forming a strong interface between the core edges and the boat plus additional sealing from water intrusion.

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The more you clean it up, the better it looks!

One way to remove the foam along the sides of the tank is a pressure washer.  Kinda messy, but makes quick work of it.  Once the sides are out, a piece of cable can be used like a saw blade to cut the foam under the tank.  

Do you have access to a fork lift or front end loader to pull on the tank with?

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Oh my...I thought my project was difficult. I didn’t go the length of cutting the deck out like that. But all of the work will be an experience and you will know your boat like no other. Good luck and I will help answer what I can along the way based on my own job.

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