Stress Crack Repair Advice

[MB242]

Hi Everyone,
Looking for advice on how to go about the stress crack repair.

Would this stuff work on such a stress crack?

Spectrum Color Yamaha Boat Black 2 Ccp 04-21 Boat Gel Coat

<p><h3><strong>*This item is non-returnable*</strong></h3></p><div style="height:200px;width:200px;border:1px solid #000;background-color:#3E3F3F;float:right"></div> <p> <b>Boat Manufacturer:</b> Yamaha<br> <b>Years Covered:</b> 2004-2011<br> <b>Color Family:</b> Black<br> <b>Color...

www.iboats.com

Also, is it a good idea to expose the stress crack some for better adhesion? Damage is to the port side of boat near the bottom. Not sure how it came about but saw it today while applying wax. I don't boat hard and tend to slow down on big aggressive waves. Does this seem like immediate concern to take care of or can wait near the end of season?

I've read multiple posts and am a newbie when it comes to gelcoat repair but have the ability to try it on my own. Am handy enough I do believe lol.

Questions I had were the following:
- After applying the paste what material is best used for covering it? I've seen multiple posts that state tape or saran wrap material. After it dries/cures do you sand the excess off? Thats the only part that throws me off.

Thanks for advice and help appreciate it!

 

[tdonoughue]

Wow. Those are some decent cracks. From the description, I thought you had spider cracks. Them ain't spider cracks.

So, to your question, first: Yes, that is the stuff you need. And yes, you will need to dremel out the cracks to widen them in order for the gelcoat to grab onto something. And then you cover it (either with Saran wrap, a piece of thin plastic, or you can spray mold release on it) to cure it. Then you wet sand (with a block) progressively with finer and finer grit until you are down to rubbing compound, polish and poof. There are a few good threads on here with pictures and everything.

All of that said, it may not be enough in your case. My concern, seeing the cracks, is what is happening with the fiberglass base behind it that is allowing this to happen? Are you missing some substructure? Or is there some damage to the glass that is letting this flex so much? I have the feeling something more is going on here, because these cracks do not look normal to me. Used to seeing impact damage and spider cracks, but not this. Plus, some of the panels caused by the cracks almost look like they are a different angles now. So if you just repair the cracks, you won't have a good result--you may need to address a wider area (talking like grind down the entire area and re-gelcoat the whole thing--a much bigger job).

Can you take us some photos of the inside? Or is it all covered?

I would also be tempted on something like this to take it to a pro to at least get a quote. They could tell you better than I can if what I am saying might be a possibility (or if I am way off base). I wouldn't want you to break out your dremel and go after this only to find a bunch of glass damage and that in the end you need to strip this all down and repair glass. That is a much bigger job, too.

 

[JTrottaNY]

Having tried to fix a similar condition on my prior boat, I can tell you that I spent days sanding down to fiberglass, rolling on several layers of gelcoat (would definitely recommend spraying if you have the ability too), sanding (use as large of a sander as possible, NOT by hand) and polishing the new gel coat out. I have a good amount of experience doing autobody work and most of the required air tools, so I was very hopeful that I could tackle the job myself. It looked "OK" (not great) for a season, the first winter when the hull got cold and then hot again about 75% of them came right back. I have come to believe that either this is really not a DIY project and/or if the fiberglass flexed in that spot to being with it will likely do the same thing again unless it is further reinforced. There was a large dock gouge in the hull that I also repaired at the same time and it did not return, go figure, which I why I fall back on the fiberglass flexing theory.

Hope you have better results than I did, but I would keep in the back of your mind that there may come a time to cut your losses and hand it over to an expert. A black hull isn't going to make things any easier to hide!

 

[FLBulldogger]

To quote @tdonoughue WOW, I have done stress cracks but DAAMMNN, I don't think I would even attempt this one. One thing I found out was that once the dremel starts you don't really know where the problem is going to lead to. On our '13 SX190 we had a couple of cracks on the top of the engine cover and when I started with the dremel it lead to places I would not have imagined. A little project turned into a big project quick and to be honest it was nothing compared to what you have in your pictures. I would recommend taking it to a pro and let them tell you what is going on there. It is going to need to be sprayed and blended carefully, on our '18 SX195 the dealer had to make repairs to the gelcoat from the PO not using fenders and the ensuing dock rash and it took them a week of repairs to get it looking good. Good luck!

 

[MB242]

Appreciate everyone's feedback gives another perspective and things to check further. Will need to shop around for a decent shop and get some quotes but wanted to use it until the season is over. Midwest (Illinois) you don't get much warm weather and want to take advantage as much as possible. You think for the next two months I should monitor it carefully and ensure it doesn't get worse with use before calling it quits on the season? Or you guys wouldn't use it at all until repaired?

Here are some more photos from the outside and will uncover it tommorow during the day to see if inside yields any discovery. Problem is the spot it's in, not sure if the battery compartment is low enough to see it from the inside.

 

[JTrottaNY]

If it were me, I would give it a heavy coat of wax and try not to let it worry you too much. Make an appointment to drop it off at the end of the season.

 

[tdonoughue]

I don't think that needs immediate repair. Not much wood at all used in these boats (and that is why in most boats an immediate repair is needed--once the gelcoat cracks, water gets in there and will migrate along the glass to wood supports and rot them). Like almost none. Plus you are mostly above the waterline.

Now, as to the cause--are you sure you or the PO did not have a loose battery? Almost looks like something impacted it from the inside...

This would still be a huge job, but if it were known to be from an impact rather than from flexing or something, at least you would have a prayer of fixing it. With these pics the area looks even bigger. You are probably talking about grinding down to the glass and relayering. That means your going to want to be spraying it (and covering with the mold release). The paste and cover with Saran wrap is really only good for individual cracks and small dings... By the time you covered this it would take you forever to sand and buff it all out at the end (thus the need for spraying--gives a more even coat from which to start the sanding, etc.).

 

[MB242]

I don't think that needs immediate repair. Not much wood at all used in these boats (and that is why in most boats an immediate repair is needed--once the gelcoat cracks, water gets in there and will migrate along the glass to wood supports and rot them). Like almost none. Plus you are mostly above the waterline.

Now, as to the cause--are you sure you or the PO did not have a loose battery? Almost looks like something impacted it from the inside...

This would still be a huge job, but if it were known to be from an impact rather than from flexing or something, at least you would have a prayer of fixing it. With these pics the area looks even bigger. You are probably talking about grinding down to the glass and relayering. That means your going to want to be spraying it (and covering with the mold release). The paste and cover with Saran wrap is really only good for individual cracks and small dings... By the time you covered this it would take you forever to sand and buff it all out at the end (thus the need for spraying--gives a more even coat from which to start the sanding, etc.).

Thinking about it some more I did put a battery jump pack in the compartment and maybe it got airborn and hit the side wall one too many times. Not sure. Will check the interior tomorrow to see if anything else points to it and ensure no heavy loose articles to be placed going forward. This makes sense why people usually see stress crack near anchor lockers right? The abuse those compartments take is alot.

Thanks for the advice, will call a few shops and see what the damage will be.
Anyone in Midwest know of a decent and honest shop??

 

[tdonoughue]

Stress cracks, or spider cracks, occur when there is stress on an area and the gelcoat just flexes enough to crack a bit. These you have are not those, nor are the ones near anchor lockers. The ones by anchor lockers (and these) look much different and are caused by impact--the anchor hitting the inside. The difference is that the impact can damage the glass below and can also break all the way through the gelcoat layer. Stress cracks can be that deep, but usually they are just at the surface (and are hard to eliminate because fixing them does not fix the underlying stress point and the crack recurs).

Stress cracks are usually nonstructural (annoying to look at, but won't harm anything). Impact cracks like these can be structural in that once the glass is damaged the area is weakened. If this were on the bottom of your boat, I would tell you not to use it until you got it fixed not because of leaks, but because of the reduced structure (come down good on a wave and you could have a problem). Not an issue on the side like this, so you should be fine for the season.

But do give us a look inside when you get there. And if you update your profile with your location, you will be able to look on the map and see others in your area...

 

[jmargo]

Do you have a fire extinguisher in there too ? Mine is in that compartment loose but I now will make sure to secure it prior to the next lake day.