Stress cracks sitting in storage

McGarnicle

So the boating headaches begin and I still have a few months before getting wet. 

Walking around my 342 this morning Ive noticed cracks developing on the port side. 

I know for a fact that these were not there in the fall and Im also pretty confident they were not there last month. My vinyl was installed last year and long story short wasn't the greatest install and have a lot of bubbles so been keeping a very close eye and would have noticed these cracks almost immediately. Usually go there once a week and today is the first time seeing them. 

My questions are this, what would cause cracks just sitting all winter? Is this something that would compromise the structural integrity? Would a survey be able to tell me the exact root cause? 

Dream_Inn

Well, I've seen several of that same type of stress crack on boats in my marina.  Found out they were most likely caused by lifting them at those points when pulling out of water.  I also found out they are stress cracks, nothing structural (I don't have any yet on my boat, but I do not get pulled very often).  

McGarnicle

It is definitely near the area the strap would be I just feel I would have noticed it in the fall, the only thing I can think of is it did happen getting pulled out but the vinyl shrinked being so cold and that's why its noticeable now. 

Michael T

They can be ground-out in a V groove manner, filled, faired and re-gelled - if not structural. I have seen a lot of this type of work done and done some myself. Annoying, worrying but fixable without big expense - just time and warm weather.

Dream_Inn

McGarnicle said:

It is definitely near the area the strap would be I just feel I would have noticed it in the fall, the only thing I can think of is it did happen getting pulled out but the vinyl shrinked being so cold and that's why its noticeable now. 

It may not have happened "when" it was pulled, but still caused by the stress of the pull-out.  I agree with what MT said & I too have seen the V-groove done with success by something that knows what they are doing.

McGarnicle

@Dream_Inn That makes sense, just a PITA because of the vinyl but just one of the joys of owning a boat. I have a fiber glass guy coming out to take a look at it when it warms up. 

Was also curious if the way the boat is sitting all winter could come into play? My marina uses foam blocks, not saying its not the proper way but I called 3 manufacturers and they did not recommend their product for my size boat. I also noticed the boat "wobbles" on the blocks when you're on it which to me seems like a lot of weight to be moving around. 

LaRea

The boat moves on the blocks when you walk on it?  That's unsat.  Make them re-block it ASAP.  

I have gelcoat cracks on my boat too.  They don't propagate.  

zaverin1

Could the be lift stress
could be in properly blocked 
Could be stress cracks caused by something inside the boat moving around 
like the galley etc 

Dream_Inn

Boat should definitely not move while on the blocks.  I've never seen the foam blocks, so not sure of that.  It does not sound like it's blocked correctly.  I agree with LaRea, have them reblock.

not sure that would cause the cracks though, as I've said a lot of that is because of the lifting with the straps.

LaRea

I did a little research on polystyrene storage blocks.  From what I can tell, they are for pontoon boats, not 8-ton cruisers.  I'd tell them right away -- in writing -- that the boat is not stable, and insist that they re-block with conventional timbers and jackstands.  

McGarnicle

Appreciate the info! I reached out to Rinker so hoping to get a call back, I'd like them to provide the recommended way for blocking a 342 so I can approach the marina that way. Its a small family owned marina and the owner and I have became good friends so no trying to start any drama. That being said though I do want to make sure my boat is stored properly and if the cracks were from sitting improperly I want to make sure its avoided going forward. 

zaverin1

Black_Diamond

My 342 sits on 6 jackstands and three wood blocks under the keel (bow, mid, stern). 

Corrected the jackstand number. 

zaverin1

Ye that’s normal for wider and larger boat 

reneechris14

I use 6 Jack stands and 3 block timbers but in not on black top. Brownell boat stands web site uses this as there standard.

Ian

I agree with what others say - foam blocks are not right for this size boat or my 310 even. And if mine moved while on it I’d be getting it reblocked irrespective. 

davidbrooks

Mine sits on 6 jack stands and two sets of wood blocks.  Last spring i noticed the exact same thing on my boat.  I called over the marina owner to get his opinion.  Never even thought it could of been caused by the sling.  I am going to have to go back and look and see where the cracks are in relation to where the straps would be.  The one thing i did though was to put tape next to each crack and measure each one.  I will go back this spring and see if the cracks grew.

zaverin1

It’s also easier to see on a color or wrapped hull compared to let’s all white 

like I said sling or something pushing or
moving inside the boat causing the stress

What side of of the boat are they on?

LaRea

Does anybody have a 342 with no gelcoat cracks?  Are cracks just a fact of life for an older heavy fiberglass cruiser that gets hauled out 1-2 times a year?  

Dream_Inn

LaRea said:

Does anybody have a 342 with no gelcoat cracks?  Are cracks just a fact of life for an older heavy fiberglass cruiser that gets hauled out 1-2 times a year?  

It's more than just the 342s.  I've seen it across the larger range of cruisers, specifically the ones at our marina large enough to use the slings.    & yes, definitely more noticeable on the darker hulls.  I'm watching to see if/when they start on mine, but again I do not get pulled yearly & I know the previous owner did not pull yearly either.

aero3113

@Dream_Inn , you keep your boat in the water Year round? 

Dream_Inn

aero3113 said:

@Dream_Inn , you keep your boat in the water Year round? 

I keep my boat on a lift year round (so about 5 feet above the water ).

Ian

I've not seen any evidence of that on our 310 since it's been slung under a travel lift the past few years for haul and launch, the clean up and buff I do I'd have seen it, especially since I had all nicks and popped voids fixed recently. I will be having a closer look though next time I am down there.

LaRea

My '03 342, sling-hauled 1-2 times a year for a decade, had gelcoat cracks when I sold it in 2013.  My '07 370, hauled 1-2 times a year since '13, has some cracks.  As far as I can tell, it's a cosmetic issue.  

Michael T

My EC 310 sat on three sets of 6X6 blocks under the keel with 4 jack stands with carpet covered 1" plywood. My EC 360 had the same set-up except it had 6 jack stands. Absolutely no to foam blocks! That boat should be rock solid on it's blocks+stands!