Suggestions for repair...

[xpertski]

Hi all, looking for your collective wisdom please!

I’m swapping engine, sold mine and the new one (from a fellow forum member) is going on next weekend. With a few days before the replacement engine arrives, I have the opportunity to correct some things on the transom. Firstly, there is some cracking in the gelcoat to the top of the transom, secondly, thoughts on the position of my current transducer?

For the cracking I was just going to cut out a v shape groove (very small one) along the cracking and full with fresh gelcoat, sand, Polish etc etc. I was told my a marine workshop it’s nothing to worry about ... do you agree - could it be water in the transom and the core expanding a bit? Should I consider a metal brace? Or is it simply just some innocent gelcoat surface cracking from a 13 year old hull?

Ps boat since had a clean .. [emoji16]

Thanks all!

[Ribtecer]

I'd be a bit concerned about that, my view is it's more than just in the gelcoat.

Does it live inside a building? At the very least I would want to get that bone dry and then get it filled with something flexible to stop water getting in there. I don't think it's currently terminal, but it will go that way if left.

Just my opinion based on those photos.

I wouldn't use gelcoat on that, as when you tighten up the bolts holding the engine on, it will crack again then letting in more water to damage it further. Make sure you get a good seal on the engine bolts as, its important water can't get inside the transom from here as well.

Let's wait and see if anyone else agrees with me.

Good luck with it.

[xpertski]

Originally Posted by Ribtecer

I'd be a bit concerned about that, my view is it's more than just in the gelcoat.



Does it live inside a building? At the very least I would want to get that bone dry and then get it filled with something flexible to stop water getting in there. I don't think it's currently terminal, but it will go that way if left.



Just my opinion based on those photos.



I wouldn't use gelcoat on that, as when you tighten up the bolts holding the engine on, it will crack again then letting in more water to damage it further. Make sure you get a good seal on the engine bolts as, its important water can't get inside the transom from here as well.



Let's wait and see if anyone else agrees with me.



Good luck with it.

Thanks Ribtecer, so perhaps use something like marine adhesive/sealant, like sikaflex?

It lives outside so limited opportunity to get it dry, but could cover the crack for a few days to let it dry out before applying sealant...

[butty]

To me it looks like the transom is not capped. That is when the top cut edge of the transom has glass fibre cloth joining the inside to the outside lapping the exposed ply core. This should be done during the build process.

Best thing is to do this before new eng8ne is fitted. Doing an isolated repair will n9t be helpful in the long run and more problems will develop. Capping with 3 layers of 450g cam over lapping front and back of transom by at least 50mm should work. Before this is done all gel coat and flow coat should be removed some the new laminate in on top of old laminate. Gel coat does not help the adhesion.

If you want more help please contact me as I am only down the road in Southampton.

Is there an issue with the current transducer location?

[Maximus]

Like others I think that is more of a problem than Gelcoat stress/cracking..Looks from the photos the Ply is delaminated through getting wet!... by changing the engine you may have just dodged a (large Calibre!) Bullet!

If it were MINE ..I'd get it as dry as poss as said..and cover completely (over sized) with a SS jacket/re-forcing plate slid over Transum sikaflexed and bolted through both sides...into fresh wood.
I've done this twice for friends Boats in the past ...and it works!....not the cheapest solution but compared to the rest...The Best.
PM me if you'd like me to put you in touch with my Guy.

[GuyC]

+1 with the comments above although I'm not a fan of the stainless steel re-inforcement.

Whilst I wouldn't fill with gelcoat, you could consider making a vee as you suggest and then filling with epoxy and microfibres.

If you expose the core, you'll be able to see whether it is wet - hopefully not.

Transducer - it's on the correct side for a normal rotation propeller and it looks about the right height. You could ensure the holes are sealed but other than that it seems OK.

Good luck and well done to Butty for offering help.

[Ribtecer]

Originally Posted by Maximus

Like others I think that is more of a problem than Gelcoat stress/cracking..Looks from the photos the Ply is delaminated through getting wet!... by changing the engine you may have just dodged a (large Calibre!) Bullet!

If it were MINE ..I'd get it as dry as poss as said..and cover completely (over sized) with a SS jacket/re-forcing plate slid over Transum sikaflexed and bolted through both sides...into fresh wood.
I've done this twice for friends Boats in the past ...and it works!....not the cheapest solution but compared to the rest...The Best.
PM me if you'd like me to put you in touch with my Guy.

I think that's good advice - l'd not thought of the stainless option. Also, as many engines are stolen with a chainsaw, this solution would slow them down as well.

A few days won't help drying it out, it wants weeks if not months of warm dry air over it - sorry, but its a fact. You'll end up trapping the moisture in there, which you don't want to do.

[HDAV]

Originally Posted by Ribtecer

I think that's good advice - l'd not thought of the stainless option. Also, as many engines are stolen with a chainsaw, this solution would slow them down as well.

Or just result in a larger section being cut out.....

Why manufacturers don’t put a couple of strips of 2” wide stainless or similar or layer it into the ply core along the transom under the gel coat at manufacture which wouldn’t cost anything but minor material costs would certainly make life more difficult for this type of theft.

[69cmw]

Originally Posted by Maximus

Like others I think that is more of a problem than Gelcoat stress/cracking..Looks from the photos the Ply is delaminated through getting wet!... by changing the engine you may have just dodged a (large Calibre!) Bullet!

If it were MINE ..I'd get it as dry as poss as said..and cover completely (over sized) with a SS jacket/re-forcing plate slid over Transum sikaflexed and bolted through both sides...into fresh wood.
I've done this twice for friends Boats in the past ...and it works!....not the cheapest solution but compared to the rest...The Best.
PM me if you'd like me to put you in touch with my Guy.

Max

What about getting it professionally fixed then get the ST steel plate on it. Belt and braces

[xpertski]

Originally Posted by butty

To me it looks like the transom is not capped. That is when the top cut edge of the transom has glass fibre cloth joining the inside to the outside lapping the exposed ply core. This should be done during the build process.

Best thing is to do this before new eng8ne is fitted. Doing an isolated repair will n9t be helpful in the long run and more problems will develop. Capping with 3 layers of 450g cam over lapping front and back of transom by at least 50mm should work. Before this is done all gel coat and flow coat should be removed some the new laminate in on top of old laminate. Gel coat does not help the adhesion.

If you want more help please contact me as I am only down the road in Southampton.

Is there an issue with the current transducer location?

Thanks Butty, will send you a PM. Thanks for your kind offer! Humber have also confirmed it needs a professional repair, they suggested not filling or using a flexible filler. Looks like it’s a good job I’ve caught this now!

[xpertski]

Thanks all for replies, I think it’s worth getting it done properly so will make some investigations on where I can have this done.

[xpertski]

Wonder if it’s worth taking away the top layer of gel coat to expose the top of the wood, see if it’s wet?

[Maximus]

Originally Posted by 69cmw

Max

What about getting it professionally fixed then get the ST steel plate on it. Belt and braces

In fairness that would be a matter for the OP and obviously everything helps ..but in terms of strength and ongoing utility...I don't think you'd nessesarly gain very much...with it dryed out as much as poss...treated ...the SS plate WELL sealed/glued i.e... on a bed of Sika with all edges filled ...and S.S bolted in place ...it would still be standing when rest of the Craft was pulp.
I'm just saying what I would do...and have done AND seen work...and on much larger much more high stress powerful RIB's

[gpsguru]

Originally Posted by xpertski

Wonder if it’s worth taking away the top layer of gel coat to expose the top of the wood, see if it’s wet?

I think that is the way forward.

Generally Gel coat stress cracks are usually 'spider cracks' which can be almost invisable under certain light conditions, however, they get more noticable over time as dirt blackens the spider crack lines.

I had them appear on my Mercury Ocean Runner transom when it was only a couple of weeks old. This was on the top of the transom and was repaired by the local boat yard under Mercury warranty. The repair was excellent and looked just like a brand new boat should look ........ when I questioned the guys that done the job, they told me the only way to do it is to sand back the gel coat to the glass fibre and then reapply a fresh gel coat.

Sand down a test Gel coat area, the Gel coat is only a couple of mm thick and then you will be able to see if it is fibre glass or bare wood underneath.

[xpertski]

Originally Posted by gpsguru

I think that is the way forward.

Generally Gel coat stress cracks are usually 'spider cracks' which can be almost invisable under certain light conditions, however, they get more noticable over time as dirt blackens the spider crack lines.

I had them appear on my Mercury Ocean Runner transom when it was only a couple of weeks old. This was on the top of the transom and was repaired by the local boat yard under Mercury warranty. The repair was excellent and looked just like a brand new boat should look ........ when I questioned the guys that done the job, they told me the only way to do it is to sand back the gel coat to the glass fibre and then reapply a fresh gel coat.

Sand down a test Gel coat area, the Gel coat is only a couple of mm thick and then you will be able to see if it is fibre glass or bare wood underneath.

Thanks for gpsguru, yes I might do that - would probably help whoever looks at it to advise fully what the issue is and level of repair needed then. [emoji106]

[IainK]

Hi All, as an increasingly experienced Avon owner nearing the end of a refurb but an experienced surveyor with structural knowledge: the diagonal failure of the rigid gelcoat suggests that the lack of top plate, has caused outward failure of the transom. the gap would have been wider and probably moved a lot under load - stop / start - so as I now know here plan for the worst. Please don't bodge it and cover up. regards iain

[xpertski]

Thanks Ian, agree, certainly won’t bodge as want this rib for many years to come, upgrading and restoring it over the next year. Thanks!

[pagick]

Part of the discovery portion of the job could have small holes drilled in to see what is wet. Once you redo your work just fill holes with epoxy. Guessing what is wet might be right- or not!

[gtflash]

Originally Posted by pagick

Part of the discovery portion of the job could have small holes drilled in to see what is wet. Once you redo your work just fill holes with epoxy. Guessing what is wet might be right- or not!

I agree, some exploratory holes. A few in the top and then where the engine bolts go.

Before filling with epoxy, decide if you are planning a polyester repair with gel coat finish or epoxy that will probably need paint or metal capping. Getting gel coat to stick to epoxy repairs can be tricky.

It is likely wet. Looks like water pools on the top too. Might be time to decide if you want the forum to see you through a transom repair or pay a man that can. Several people done them now.

[pagick]

One last tip. If you are putting on a metal cap, sand down to fiberglass where the cap covers. Then put bondo body filler in the metal channel and use it as a filler of any voids and a glue. But still bolt it on. This is how I attach anything to the hull. Like installing it a tower on a wakeboard boat. I would use a backer plate that has bondo on one side, against the interior fiberglass. Then bolt the new fixture to the backer plate from the outside. It helps a lot with spider cracking the gelcote. Since your backer plate becomes a 100% contact fit.