Crack in fiberglass at seam in engine compartment!?

[Eric Popper]

Today I was out on the lake and checking things in the engine compartment. I noticed a crack in the gel coat along the seam where the forward transom meets the floor of the compartment (at the front of the compartment, closest to the rear seat). It appeared that the wood or raw fiberglass underneath was visible in about a 1/8 inch wide area along parts of this crack. I haven't noticed this before.

I was going to take a picture but it ended up being too dark as it was the end of the day.

Has anyone else seen such a thing?

Eric

 

[ToddW850]

I don't believe I have noticed anything in this area. When you have a chance to take a pic in the daylight and we can check exactly where you're talking and see it.

 

[Murf'n'surf]

That doesn't sound good...post a pic.

 

[Glassman]

Today I was out on the lake and checking things in the engine compartment. I noticed a crack in the gel coat along the seam where the forward transom meets the floor of the compartment (at the front of the compartment, closest to the rear seat). It appeared that the wood or raw fiberglass underneath was visible in about a 1/8 inch wide area along parts of this crack. I haven't noticed this before.

I was going to take a picture but it ended up being too dark as it was the end of the day.

Has anyone else seen such a thing?

Eric

Sounds like you are describing a bulkhead....a picture would be nice, I'm sure you'll get around to it when you have daylight. When you do, take a look at the bottom. It's not unusual to see stress fractures due to hull strikes flexing the hull away from a stringer or bulkhead. If there is no evidence of a hard strike (grounding, etc.) you might have maybe at one time or another come down real hard off a wave or wake crossing..? Possible?

 

[Eric Popper]

I thought I was heading back to the lake tomorrow but I think the day is going to go a different direction. The boat has only been beached once that I am aware of and I walked it into the sand. We do hit some hard wake sometimes on our lake. We did hit one of the harder thuds that I have felt on our last outing crossing a wake too....

I haven't seen the bottom of the boat yet.

Photos will come soon. I am very concerned that there may be structural damage.

E

 

[Bruce]

I have hit lots and lots of waves hard without any damage.

Hopefully we can identify what has happened from pictures and it does not delay your boating plans.

 

[Ronnie]

I assume you are talking about the bulkhead separating the engine compartment from the fuel tank. I may be wrong but I think that the engine compartment makes up the rear of/is in the inner hull of the boat. For comparison, the area under the clean out ports and behind the engine compartment is bound by a single/exterior hull. I wouldn't be as concerned about a crack at the seam of the inner hull. Pics would help immensely.

 

[CrankyGypsy]

@Ronnie is correct: the engine compartment is an inner hull. in the bottom-most part of the engine bay, there is almost an inch of distance to the outer hull. but as you move closer to the sides, this distance tapers pretty quickly and is supported by what could be considered "glue stringers" about halfway up. I've found that the outer hull here can flex but the floor of the engine bay is more rigid, and therefore will succumb to stress easier.

 

[Glassman]

The Yamaha boats are comprised of two major components - Hull and Deck (sometimes called the Cap) There is no "Inner Hull" that is actually the Deck. It is glued to the hull - that's the part that rides on the water.
So while the engine sits in a deep recess in the deck, it's mounted to the deck which is glued to the outer portion of the boat (hull) for a very solid construction. They use a very strong urethane adhesive that stays somewhat flexible and helps absorb vibration and shock. The same material can be seen in various places throughout the boat. It might be the seaming material that @Eric Popper is looking at and if that's the case it's easy to repair. A picture will tell for sure.

Here are some interesting videos some of you may enjoy:

First Yamaha - it shows "some" of the construction process. You will see the masked tooling getting gel coat applied and a finished deck getting cut. Ultimately those two parts are glued together.
Now we have it from the horses mouth; Yamaha lake tests EVERY boat prior to sale. That's what I thought and now have confirmed.

Next up, Axis Boats. They are not automated as Yamaha is. You will get a better idea of how a deck and hull are glued together. Also a good example of the difference between man and machine. The Axis boat construction method appears to me to rely primarily on chopper gun construction. A method that chops fiberglass strand into small lengths and mixes it with atomized resin as it is blown into the mold. It then gets rolled out by hand. Not the method I prefer when creating a hull. I prefer the Boston Whaler lay-up schedule personally and that's how I have constructed small boats here in my dungeon .

 

[Eric Popper]

So here are the pics. I looked the whole boat over, especially the outside of the hull and found no other issues. The pictures are of the joint of the forward bulkhead of the engine compartment (separates fuel compartment) and the floor of the engine compartment. When I looked closely and ran my hand along the joint, it seems that the gelcoat is weak all along the joint. I don't know if this is just a function of manufacturing and finishing or some sort of indication of a more serious problem.

 

[jetboater4life]

Looks like it has been there a while since it appears someone tried to smear something over it, silicone maybe? Are you sure that it just happened?

 

[Eric Popper]

Derek,

I didn't even look at my own photos that closely as I just got off of the lake. You're right. The question then is was this done at the factory to cover an imperfection or did the prior owner try to cover something bad up? I will say that the boat was obviously very well cared for by the prior owner and in great shape when I purchased it.

I'm probably just being too anal, but I'm sure someone here will know why that's like that....

Great day out today. Beautiful weather and the water was great.

irst time we got our 1 year old black lab swimming. She wouldn't come near me for an hour after I put her in the water though... She did enjoy standing on the inter tube and watching the kids splash around.

E

 

[Murf'n'surf]

I would like to see pic 5 in better light and focus more on that crack. Looks like its never been touched after manufacturing to me.
Can you get a crowbar or driver in there to see if anything moves? Definitely needs to be sealed up. Weather the fiberglass moves or not might sway me between a sealant and laying glass mat in there to strengthen it.

 

[Glassman]

No biggy. That's the gel coat cracking. It was applied over the seaming material. That material can flex, popping off the gel coat. You can clean it up and make it look pretty again if you like. Or clean it up and go boating.