Northcraft Transom Failure

[Bigmuz7]

After only 80 hours use, my Northcraft transom has had enough.. for an 8.5M boat and rated to 300hp, my 275 Verado has been too much for it, and the transom has failed. I only do 'light cruising' and it is clear the transom has failed due to a manufacturing defect. Thankfully my dealer is sorting out Northcrafts shortfalls, all be it, much more slowly than I would have liked ..But ..finally ... I am satisfied.. their methods are correct .. my question is .. as the boat was coded to Cat B spec on purchase, how did Northcraft obtain this coding in the first place?and after the dealers modifications... how do I retain it ?.. shouldn't they retest it?

It should be said.. Northcraft were asked to repair the transom failure after it was noticed,.. and their effort was nothing short of laughable.. They have produced a great hull (copy) but have blamed this hull failure on the Verado and its installation..

Its the last Northcraft I'll be buying .....And this is my 3rd ...

Disappointed owner

[Downhilldai]

What has actually failed and what is being done to remedy it?

[codprawn]

Sorry to hear about that - how about some pics - what kind of failiure are we talking?

[Bigmuz7]

Its suffered a delamination due to a lack of bonding /or strength from the stiffenening knees that support it

[codprawn]

Worrying but shouldn't be too hard a job to fix??

[Bigmuz7]

Originally Posted by codprawn

Worrying but shouldn't be too hard a job to fix??

Well they have completely relaminated the transom and have removed the stiffening knees, to be replaced by two stainless struts which will be connected to brackets which are bolted to the bearers (which are bonded to the hull) under the floor. IMO it will be stronger than the original.

[Richard B]

It looks suspiciously like (as per JW's advice to Bruce B on consoles) that your "knees" are only bonded to the surface lamination on the inside of the transom. Given that you (or the fitter) had added a steel plate to the back of the transom for the o/b, it seems difficult to reasonably argue that the outboard installation is to blame!

Edit - is that ply all sealed? Looks a bit "naked" in the pic!

[Bigmuz7]

Originally Posted by Richard B

It looks suspiciously like (as per JW's advice to Bruce B on consoles) that your "knees" are only bonded to the surface lamination on the inside of the transom. Given that you (or the fitter) had added a steel plate to the back of the transom for the o/b, it seems difficult to reasonably argue that the outboard installation is to blame!

Edit - is that ply all sealed? Looks a bit "naked" in the pic!

Yes the original bonding of the knees was the problem .. they didnt have a good bond to the transom .... a slight misgiving on such a craft I am really Pissed off at how Northcraft have dealt with this though .. you should have seen how they attempted to repair it

A survey proved there to be large boss areas either side of the knees, on the first photo

.. yes Richard the bearers are sealed ok,.totally glassed,.. or as far as I can tell anyway

[jwalker]

Originally Posted by Bigmuz7

Yes the original bonding of the knees was the problem .. they didnt have a good bond to the transom ....

The bond between the fibreglass and the transom ply may or may not be the best but a bond between ply and fibreglass is always poor. The ply should not be the main strength of the transom. In a way, the ply is just a filler and spacer between two sturdy layers of fibreglass to make for rigidity and in your case the fibreglass has not been sturdy enough. I can't see a problem with the original knees. The laminating around them appears intact in your first photo. It is the laminating over the surface of the transom which has failed. The knees also look to be about 50mm thick and fairly substantial. Of course, I can't see the original joining of the knees to the deck and hull structure. Be mindful that strengthening one area transfers the load to another area.

I'm not going to comment on the method of repair but....

[Downhilldai]

Who's doing/done the work on it?