Soft floor

[Rickhern]

Hey Gang,

Just about to pull the trigger on this 87 offshore 24. The 250 merc has 560 hours and meticulous maintenance. The only issue i can see (feel) is a bit of softness just behind the starboard pedestal storage. Any idea how serious of a repair this might be or is it even needed. The boat has always been trailered. Took it for a test ride and ran great. Appreciate any help.

 

[PointedRose]

Hey Gang,

Just about to pull the trigger on this 87 offshore 24. The 250 merc has 560 hours and meticulous maintenance. The only issue i can see (feel) is a bit of softness just behind the starboard pedestal storage. Any idea how serious of a repair this might be or is it even needed. The boat has always been trailered. Took it for a test ride and ran great. Appreciate any help.

Depends on how long you plan to keep the boat. I’d not be TOO concerned about it, except that it suggest some water intrusion, which could make its way down to the fuel tank which would be a bigger job if not done in recent history of the boat. It’s not a terrible job if you end up needing to fix a bit of the floor.

 

[Rickhern]

The owner had the tank epoxy coated 3 years ago. Interesting, he said the tank is 60 gallon. Specs say 93 with a 55 aux available. When I looked in the forward hatch there was no aux tank.

 

[PointedRose]

The owner had the tank epoxy coated 3 years ago. Interesting, he said the tank is 60 gallon. Specs say 93 with a 55 aux available. When I looked in the forward hatch there was no aux tank.

PO maybe just considered 60 more than adequate for the single outboard. Mine is 60. Maybe needed the storage for other things or used for a live well or something else entirely. You could always add in a new aux tank

 

[trapper]

Rickhern, Are you sure about the "meticulous maintenance" on the the Merc. It appears the area in the photo has not had the same maintenance ...just saying. Hope it all works out for the best!

 

[glacierbaze]

Tank should have capacity on the label, under one of the round pie plates. Did he replace the tank, or just coat and reuse? Is the tank located in the main tank space, or the aux tank space?

 

[Rickhern]

Rickhern, Are you sure about the "meticulous maintenance" on the the Merc. It appears the area in the photo has not had the same maintenance ...just saying. Hope it all works out for the best!

Yes, have all service records. He used the boat just to cruise the bay and had installed a carpet over the floor. This was the first time he had pulled it back in years.

 

[Rickhern]

Tank should have capacity on the label, under one of the round pie plates. Did he replace the tank, or just coat and reuse? Is the tank located in the main tank space, or the aux tank space?

He had it coated. The specs show a 93 in back with an optional 55 in front. There is nothing in front. I just spoke with him, says he thinks its 60 but he never put more than that in it, maybe larger. My guess is it is the original 93.

 

[PointedRose]

Yes, have all service records. He used the boat just to cruise the bay and had installed a carpet over the floor. This was the first time he had pulled it back in years.

That carpet would have held moisture, so the soft floor isn’t surprising. I don’t understand why people put carpets in boats tbh

 

[Rickhern]

That carpet would have held moisture, so the soft floor isn’t surprising. I don’t understand why people put carpets in boats tbh

How difficult a repair?

 

[DennisG01]

That's kind of an odd place to have a soft spot. There are no direct core "compromises" nearby. Just having water setting on top of the deck shouldn't cause an issue. Possibly the fiberglass skin underneath the wood core wasn't sealed well (or just separated over 35 years... which is understandable) and it allowed moisture in that way and started to cause delamination.

Your skill set will determine "how difficult" it will be, so that's a hard one to answer. What I can tell you, though, is you should count on the soft spot to be at least 3 times larger than what you think it is.

This is my boat - to give you an idea of what's underneath:

(Having trouble with pics - will post later)

 

[Rickhern]

That's kind of an odd place to have a soft spot. There are no direct core "compromises" nearby. Just having water setting on top of the deck shouldn't cause an issue. Possibly the fiberglass skin underneath the wood core wasn't sealed well (or just separated over 35 years... which is understandable) and it allowed moisture in that way and started to cause delamination.

Your skill set will determine "how difficult" it will be, so that's a hard one to answer. What I can tell you, though, is you should count on the soft spot to be at least 3 times larger than what you think it is.

This is my boat - to give you an idea of what's underneath:

(Having trouble with pics - will post later)

Thanks, looking forward to the pics.

 

[Fishtales]

A boat of that vintage is bound to have some core issues. If you can get at it easy, that type of repair is fairly easy to do. Check out the west system at West Marine. Lots of vids on youtube that detail how to do that type of repair. If you can get the boat cheap enough and you have access, I'd go for it.

 

[DennisG01]

 

[Halfhitch]

Zowie!!! What a project!

 

[hooked on Grady]

As I was scrolling down I was thinking the whole floor could be shot with carpet over it. Then I got to Dennis's pic. thats what I was thinking you may find. That is a major project to start out with. someone must have replaced the tank at some point. My offshore has 2 93 gallon tanks in it. both appear to have been the original size based on the space they are in as there have been no alterations. I just removed the front tank, cleaned and painted the space. I had to repair the aft tank cover as the floor was soft but the front was fine.

 

[PointedRose]

How difficult a repair?

Dennis laid it out pretty well. To do it right is tearing it apart and building it back up with solid material. There’s also various patches that could be done to improve the existing. Like Dennis said you can cut out the ‘skin’ and remove the rotted core area, replace, and then epoxy the skin back in place. More of a patch would be drilling holes maybe a half inch deep, about 6 inches apart, and use gitrot or cpes penetrating epoxy with syringes and then patching over the holes with marinetex or the like.
lots of internet videos and threads on this topic for research.
if it’s not that bad, I’d just leave it and try to upgrade the boat in a couple years and unload to someone else. Definitely get rid of the rug though.

Rot Repair in Glass Boats - The Rot Doctor

How to use epoxies to repair or replace transoms, floors, stringers and supports, engine bed mounts, wood-cored decks, delamination and other problem areas.

www.rotdoctor.com

Fiberglass Boat Repair and Maintenance Book | West Marine

Check out our Fiberglass Boat Repair and Maintenance Book and more from West Marine!

www.westmarine.com

 

[DennisG01]

To better explain my situation...

My boat was originally a stern drive model and only had/has the forward 90-some gallon tank. If you look at the picture, you can see the "wider" cutout/hole where the sterndrive and the "dogbox" would have been. The perimeter of the that cutout had an exposed core - or atleast it was very poorly sealed (either from the factory or during the OB mod). Water migrated from that "engine hole" forward. The soft spot was only about a foot or two square, but once opened up, the soft wood covered a much larger area. Closer to the fish boxes, the wood was perfectly fine... but you know the 'ol saying "As long as you're in there"

I rebuilt the floor "layout" somewhat - I built a new hatch to fit the new layout in the back that matched the width of the original hatch (the green, fiberglass L-channel is the start of the new hatch) and also built a flip-up table (simple/crude, but it works) that covers the vertical "hole". A little tip... to build the new hatch, I laid the L-channel in place and then just used a few small pieces of glass on the corners and dribbled some superglue on the glass to hold it in position while I took it back to the workbench so as not to loose the "shape".

 

[Rickhern]

Great job! Thanks for the info.

 

[DennisG01]

Zowie!!! What a project!

It was actually a fun project. I did it over the winter -- see the heater in the first pic? I built a high frame for the shrink wrapping (basically, the whole back end of the boat was big box with plenty of headroom. I even installed shop lighting under the roof of the frame - that first picture was taken at night.

Rick, I hope those pics don't scare you - I posted them, primarily, so you can get a better understanding of how things are put together. Plus, everyone likes construction pics!