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Water Leak through gel coat repair

bttally

Jet Boat Addict
Messages
63
Reaction score
74
Points
97
Location
North Florida
Boat Make
Yamaha
Year
2023
Boat Model
FSH Sport
Boat Length
22
I bought a 2017 AR190 two months ago that was is great condition with only 40 hours. I have been reading the forums for a while and have learned how to do just about everything from this forum. The only issue with my boat was a gouge in the gel coat. The original owner had patched it with some silicone and left it alone. I sanded the rut out and filled and patched it with Spectrum Gel Coat Paste and it looked great. After the repair was cleaned up and polished I noticed that water slowly drips through the repair. After a few days of drips I opened the part back up that was dripping with a dremel and let it dry out. I then repaired the smaller area with Marine Tex this time. I made the repair a little wider and thicker just to seal the area but water is dripping through again.

Anyone experience this? The fiberglass is not soggy and is still firm.

Also, as a side question...does anyone have the number of the K&N Spark Arrestor Air Filer that fits? I can't find it searching the forums or the K&N site. I removed the ribbon and would like to be compliant just in case.

Thanks!
Ben
 

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You need to grind out 3 inches or more around the patch including grind the patch to the fiberglass, use dr fuser heat set following the procedure of how to cure it writen on the tube. Sand it prime it, and paint it (most boat shops can give you the paint code) and apply the gel coat 10" or more past the repair. You can wetsand and buff it and it will look like new. It's a long process, I've repaired a few boats and fiberglass vehicles.
Others will have their opinions as well. As a collision repair tech that is what I would do for a lasting repair.
Goodluck. I'm looking fwd to seeing everyones opinions.
 
You need to grind out 3 inches or more around the patch including grind the patch to the fiberglass, use dr fuser heat set following the procedure of how to cure it writen on the tube. Sand it prime it, and paint it (most boat shops can give you the paint code) and apply the gel coat 10" or more past the repair. You can wetsand and buff it and it will look like new. It's a long process, I've repaired a few boats and fiberglass vehicles.
Others will have their opinions as well. As a collision repair tech that is what I would do for a lasting repair.
Goodluck. I'm looking fwd to seeing everyones opinions.
@Tyler jones .....great tips. While gel coat is never a total water barrier (I believe in waxing hulls) and if your boat is going to be left in the water repeatedly for lengthy periods of time a bottom barrier coat may be a good idea - that said gel coat should not leak as @bttally has described. In my opinion one of the most important areas of marine fiberglass repair is to absolutely ensure there is no moisture in the area to be repaired as water in fiberglass and fiberglass cores attracts more water. Also there can be no voids in the area you are repairing or they too attract water. @bttally - is your surface gel coat or Yamaha marine paint? My 2018 Yamaha waverunner's black hull was Nano Xcel 2 covered with a top coat of marine paint. I was told by Yamaha U.S.A and RIVA Florida that you were supposed to treat it like a normal fiberglass repair then spray paint it followed a few weeks later by a good waxing. I suspect the colored hull of my 2020 SX195 is Yamaha marine paint too. Dry - repair - spray paint - wax area or bottom barrier coat!
 
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@Tyler jones when I google dr fuser heat set I am not getting any results. Where can I find this?

@Canuckjetboater from what I have read on this forum it is gel coat not marine paint but I could be wrong. There are numerous threads on repairing gel coat chips which helped me through the process.

Any tips for drying? I used the dremel to grind it out and left a fan on it for several days until it was all dry. The moisture didn't appear until the gel coat or the marine tex was put over the hole. At that point moisture starts to seep through even while the coating is still wet. It is not a lot. Maybe a couple drips a day accumulate and then run down. For a while I thought I had water held in the hull, but after raising the nose way up I'm not getting any water out.
 
@Tyler jones when I google dr fuser heat set I am not getting any results. Where can I find this?

@Canuckjetboater from what I have read on this forum it is gel coat not marine paint but I could be wrong. There are numerous threads on repairing gel coat chips which helped me through the process.

Any tips for drying? I used the dremel to grind it out and left a fan on it for several days until it was all dry. The moisture didn't appear until the gel coat or the marine tex was put over the hole. At that point moisture starts to seep through even while the coating is still wet. It is not a lot. Maybe a couple drips a day accumulate and then run down. For a while I thought I had water held in the hull, but after raising the nose way up I'm not getting any water out.
@bttally .....unfortunately getting the water out of fiberglass takes time. You can direct warm air - not too hot - or you'll damage the surrounding finish. There could be fairly significant water penetration into the fiberglass surrounding this area. Fiberglass and its resins draw water into them by nature and the area must be dried thoroughly. If in doubt a moisture meter could be used.
 
@bttally .....unfortunately getting the water out of fiberglass takes time. You can direct warm air - not too hot - or you'll damage the surrounding finish. There could be fairly significant water penetration into the fiberglass surrounding this area. Fiberglass and its resins draw water into them by nature and the area must be dried thoroughly. If in doubt a moisture meter could be used.
I took the dremel out tonight and opened it up a little on the end where the water was coming from. Everything looks bone dry. Its dusty as I'm grinding and no sign of water. I set up a little heater to try to dry it out. I'm in North Florida though with 200% humidity and rain 3 times a day. I may try this for a week and then seal it up. May have to wait for fall to open it all the way up and get it truly dry.
 

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I took the dremel out tonight and opened it up a little on the end where the water was coming from. Everything looks bone dry. Its dusty as I'm grinding and no sign of water. I set up a little heater to try to dry it out. I'm in North Florida though with 200% humidity and rain 3 times a day. I may try this for a week and then seal it up. May have to wait for fall to open it all the way up and get it truly dry.
@bttally .....understood. Yes, high humidity makes drying-out a fiberglass repair area and patching it much more challenging. Hope this patch works well!
 
I do apologize it is called lord fuser T21.
When it is applied its slightly runny but not bad, after you apply it you heat it up with a heat gun and it becomes rock hard but still has enough hive it will not break under extreme conditions. I'm a believer in the product after seeing a repair hold better than the fiberglass structure it was adhered to break before the fuser.
 
I do apologize it is called lord fuser T21.
When it is applied its slightly runny but not bad, after you apply it you heat it up with a heat gun and it becomes rock hard but still has enough hive it will not break under extreme conditions. I'm a believer in the product after seeing a repair hold better than the fiberglass structure it was adhered to break before the fuser.
Thanks! I'm going to look it up. After two days with the fan it was still dry but then I went out of town and left it for a few days with no fan. When I got back tonight it was all wet again. Back to the heater and fan. Hopefully I'll get it to dry out this week.
 
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